diff --git a/tests/NestedSetsBehaviorTest.php b/tests/NestedSetsBehaviorTest.php
index aa46e34..1867275 100644
--- a/tests/NestedSetsBehaviorTest.php
+++ b/tests/NestedSetsBehaviorTest.php
@@ -7,7 +7,7 @@
 
 namespace tests;
 
-use tests\models\MultipleRootsTree;
+use tests\models\MultipleTree;
 use tests\models\Tree;
 use Yii;
 use yii\db\Connection;
@@ -27,13 +27,13 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node = new Tree(['name' => 'Root']);
         $this->assertTrue($node->makeRoot());
 
-        $node = new MultipleRootsTree(['name' => 'Root 1']);
+        $node = new MultipleTree(['name' => 'Root 1']);
         $this->assertTrue($node->makeRoot());
 
-        $node = new MultipleRootsTree(['name' => 'Root 2']);
+        $node = new MultipleTree(['name' => 'Root 2']);
         $this->assertTrue($node->makeRoot());
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-make-root-new.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -52,10 +52,10 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node = new Tree(['name' => 'New node']);
         $this->assertTrue($node->prependTo(Tree::findOne(9)));
 
-        $node = new MultipleRootsTree(['name' => 'New node']);
-        $this->assertTrue($node->prependTo(MultipleRootsTree::findOne(31)));
+        $node = new MultipleTree(['name' => 'New node']);
+        $this->assertTrue($node->prependTo(MultipleTree::findOne(31)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-prepend-to-new.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -74,10 +74,10 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node = new Tree(['name' => 'New node']);
         $this->assertTrue($node->appendTo(Tree::findOne(9)));
 
-        $node = new MultipleRootsTree(['name' => 'New node']);
-        $this->assertTrue($node->appendTo(MultipleRootsTree::findOne(31)));
+        $node = new MultipleTree(['name' => 'New node']);
+        $this->assertTrue($node->appendTo(MultipleTree::findOne(31)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-append-to-new.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -96,10 +96,10 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node = new Tree(['name' => 'New node']);
         $this->assertTrue($node->insertBefore(Tree::findOne(9)));
 
-        $node = new MultipleRootsTree(['name' => 'New node']);
-        $this->assertTrue($node->insertBefore(MultipleRootsTree::findOne(31)));
+        $node = new MultipleTree(['name' => 'New node']);
+        $this->assertTrue($node->insertBefore(MultipleTree::findOne(31)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-before-new.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -127,10 +127,10 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node = new Tree(['name' => 'New node']);
         $this->assertTrue($node->insertAfter(Tree::findOne(9)));
 
-        $node = new MultipleRootsTree(['name' => 'New node']);
-        $this->assertTrue($node->insertAfter(MultipleRootsTree::findOne(31)));
+        $node = new MultipleTree(['name' => 'New node']);
+        $this->assertTrue($node->insertAfter(MultipleTree::findOne(31)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-after-new.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -155,11 +155,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
 
     public function testMakeRootExists()
     {
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
         $this->assertTrue($node->makeRoot());
 
-        $dataSet = $this->getConnection()->createDataSet(['multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-make-root-exists.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -178,7 +178,7 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
      */
     public function testMakeRootExistsExceptionIsRaisedWhenItsRoot()
     {
-        $node = MultipleRootsTree::findOne(23);
+        $node = MultipleTree::findOne(23);
         $node->makeRoot();
     }
 
@@ -188,11 +188,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->prependTo(Tree::findOne(2)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->prependTo(MultipleRootsTree::findOne(24)));
+        $this->assertTrue($node->prependTo(MultipleTree::findOne(24)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-prepend-to-exists-up.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -203,22 +203,22 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->prependTo(Tree::findOne(16)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->prependTo(MultipleRootsTree::findOne(38)));
+        $this->assertTrue($node->prependTo(MultipleTree::findOne(38)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-prepend-to-exists-down.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
 
     public function testPrependToExistsAnotherTree()
     {
-        $node = MultipleRootsTree::findOne(9);
+        $node = MultipleTree::findOne(9);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->prependTo(MultipleRootsTree::findOne(53)));
+        $this->assertTrue($node->prependTo(MultipleTree::findOne(53)));
 
-        $dataSet = $this->getConnection()->createDataSet(['multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-prepend-to-exists-another-tree.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -256,11 +256,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->appendTo(Tree::findOne(2)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->appendTo(MultipleRootsTree::findOne(24)));
+        $this->assertTrue($node->appendTo(MultipleTree::findOne(24)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-append-to-exists-up.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -271,22 +271,22 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->appendTo(Tree::findOne(16)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->appendTo(MultipleRootsTree::findOne(38)));
+        $this->assertTrue($node->appendTo(MultipleTree::findOne(38)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-append-to-exists-down.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
 
     public function testAppendToExistsAnotherTree()
     {
-        $node = MultipleRootsTree::findOne(9);
+        $node = MultipleTree::findOne(9);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->appendTo(MultipleRootsTree::findOne(53)));
+        $this->assertTrue($node->appendTo(MultipleTree::findOne(53)));
 
-        $dataSet = $this->getConnection()->createDataSet(['multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-append-to-exists-another-tree.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -324,11 +324,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->insertBefore(Tree::findOne(2)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertBefore(MultipleRootsTree::findOne(24)));
+        $this->assertTrue($node->insertBefore(MultipleTree::findOne(24)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-before-exists-up.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -339,22 +339,22 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->insertBefore(Tree::findOne(16)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertBefore(MultipleRootsTree::findOne(38)));
+        $this->assertTrue($node->insertBefore(MultipleTree::findOne(38)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-before-exists-down.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
 
     public function testInsertBeforeExistsAnotherTree()
     {
-        $node = MultipleRootsTree::findOne(9);
+        $node = MultipleTree::findOne(9);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertBefore(MultipleRootsTree::findOne(53)));
+        $this->assertTrue($node->insertBefore(MultipleTree::findOne(53)));
 
-        $dataSet = $this->getConnection()->createDataSet(['multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-before-exists-another-tree.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -401,11 +401,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->insertAfter(Tree::findOne(2)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertAfter(MultipleRootsTree::findOne(24)));
+        $this->assertTrue($node->insertAfter(MultipleTree::findOne(24)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-after-exists-up.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -416,22 +416,22 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         $node->name = 'Updated node 2';
         $this->assertTrue($node->insertAfter(Tree::findOne(16)));
 
-        $node = MultipleRootsTree::findOne(31);
+        $node = MultipleTree::findOne(31);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertAfter(MultipleRootsTree::findOne(38)));
+        $this->assertTrue($node->insertAfter(MultipleTree::findOne(38)));
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-after-exists-down.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
 
     public function testInsertAfterExistsAnotherTree()
     {
-        $node = MultipleRootsTree::findOne(9);
+        $node = MultipleTree::findOne(9);
         $node->name = 'Updated node 2';
-        $this->assertTrue($node->insertAfter(MultipleRootsTree::findOne(53)));
+        $this->assertTrue($node->insertAfter(MultipleTree::findOne(53)));
 
-        $dataSet = $this->getConnection()->createDataSet(['multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-insert-after-exists-another-tree.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -475,9 +475,9 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
     public function testDeleteWithChildren()
     {
         $this->assertEquals(7, Tree::findOne(9)->deleteWithChildren());
-        $this->assertEquals(7, MultipleRootsTree::findOne(31)->deleteWithChildren());
+        $this->assertEquals(7, MultipleTree::findOne(31)->deleteWithChildren());
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-delete-with-children.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -494,9 +494,9 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
     public function testDelete()
     {
         $this->assertEquals(1, Tree::findOne(9)->delete());
-        $this->assertEquals(1, MultipleRootsTree::findOne(31)->delete());
+        $this->assertEquals(1, MultipleTree::findOne(31)->delete());
 
-        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_roots_tree']);
+        $dataSet = $this->getConnection()->createDataSet(['tree', 'multiple_tree']);
         $expectedDataSet = $this->createFlatXMLDataSet(__DIR__ . '/data/test-delete.xml');
         $this->assertDataSetsEqual($expectedDataSet, $dataSet);
     }
@@ -543,8 +543,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-parents-multiple-roots.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(33)->parents()->all())
+            require(__DIR__ . '/data/test-parents-multiple-tree.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(33)->parents()->all())
         );
 
         $this->assertEquals(
@@ -553,8 +553,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-parents-multiple-roots-with-depth.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(33)->parents(1)->all())
+            require(__DIR__ . '/data/test-parents-multiple-tree-with-depth.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(33)->parents(1)->all())
         );
     }
 
@@ -566,8 +566,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-children-multiple-roots.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(31)->children()->all())
+            require(__DIR__ . '/data/test-children-multiple-tree.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(31)->children()->all())
         );
 
         $this->assertEquals(
@@ -576,8 +576,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-children-multiple-roots-with-depth.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(31)->children(1)->all())
+            require(__DIR__ . '/data/test-children-multiple-tree-with-depth.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(31)->children(1)->all())
         );
     }
 
@@ -589,8 +589,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-leaves-multiple-roots.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(31)->leaves()->all())
+            require(__DIR__ . '/data/test-leaves-multiple-tree.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(31)->leaves()->all())
         );
     }
 
@@ -602,8 +602,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-prev-multiple-roots.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(31)->prev()->all())
+            require(__DIR__ . '/data/test-prev-multiple-tree.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(31)->prev()->all())
         );
     }
 
@@ -615,8 +615,8 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-next-multiple-roots.php'),
-            ArrayHelper::toArray(MultipleRootsTree::findOne(31)->next()->all())
+            require(__DIR__ . '/data/test-next-multiple-tree.php'),
+            ArrayHelper::toArray(MultipleTree::findOne(31)->next()->all())
         );
     }
 
@@ -628,11 +628,11 @@ class NestedSetsBehaviorTest extends DatabaseTestCase
 
     public function testIsChildOf()
     {
-        $node = MultipleRootsTree::findOne(26);
-        $this->assertTrue($node->isChildOf(MultipleRootsTree::findOne(25)));
-        $this->assertTrue($node->isChildOf(MultipleRootsTree::findOne(23)));
-        $this->assertFalse($node->isChildOf(MultipleRootsTree::findOne(3)));
-        $this->assertFalse($node->isChildOf(MultipleRootsTree::findOne(1)));
+        $node = MultipleTree::findOne(26);
+        $this->assertTrue($node->isChildOf(MultipleTree::findOne(25)));
+        $this->assertTrue($node->isChildOf(MultipleTree::findOne(23)));
+        $this->assertFalse($node->isChildOf(MultipleTree::findOne(3)));
+        $this->assertFalse($node->isChildOf(MultipleTree::findOne(1)));
     }
 
     public function testIsLeaf()
diff --git a/tests/NestedSetsQueryBehaviorTest.php b/tests/NestedSetsQueryBehaviorTest.php
index e3aa0b2..03a6eaf 100644
--- a/tests/NestedSetsQueryBehaviorTest.php
+++ b/tests/NestedSetsQueryBehaviorTest.php
@@ -7,7 +7,7 @@
 
 namespace tests;
 
-use tests\models\MultipleRootsTree;
+use tests\models\MultipleTree;
 use tests\models\Tree;
 use Yii;
 use yii\db\Connection;
@@ -26,8 +26,8 @@ class NestedSetsQueryBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-roots-multiple-roots-query.php'),
-            ArrayHelper::toArray(MultipleRootsTree::find()->roots()->all())
+            require(__DIR__ . '/data/test-roots-multiple-tree-query.php'),
+            ArrayHelper::toArray(MultipleTree::find()->roots()->all())
         );
     }
 
@@ -39,8 +39,8 @@ class NestedSetsQueryBehaviorTest extends DatabaseTestCase
         );
 
         $this->assertEquals(
-            require(__DIR__ . '/data/test-leaves-multiple-roots-query.php'),
-            ArrayHelper::toArray(MultipleRootsTree::find()->leaves()->all())
+            require(__DIR__ . '/data/test-leaves-multiple-tree-query.php'),
+            ArrayHelper::toArray(MultipleTree::find()->leaves()->all())
         );
     }
 
diff --git a/tests/data/clean.xml b/tests/data/clean.xml
index 5e8e422..d3bb6bf 100644
--- a/tests/data/clean.xml
+++ b/tests/data/clean.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <dataset>
     <tree/>
-    <multiple_roots_tree/>
+    <multiple_tree/>
 </dataset>
diff --git a/tests/data/test-append-to-exists-another-tree.xml b/tests/data/test-append-to-exists-another-tree.xml
index 4829d14..fd835eb 100644
--- a/tests/data/test-append-to-exists-another-tree.xml
+++ b/tests/data/test-append-to-exists-another-tree.xml
@@ -1,69 +1,69 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <dataset>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="45" lft="29" rgt="42" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="10" tree="45" lft="30" rgt="35" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="45" lft="31" rgt="32" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="45" lft="33" rgt="34" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="45" lft="36" rgt="41" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="45" lft="37" rgt="38" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="45" lft="39" rgt="40" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="43" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="45" lft="29" rgt="42" depth="2" name="Updated node 2"/>
+    <multiple_tree id="10" tree="45" lft="30" rgt="35" depth="3" name="Node 2.1"/>
+    <multiple_tree id="11" tree="45" lft="31" rgt="32" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="45" lft="33" rgt="34" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="45" lft="36" rgt="41" depth="3" name="Node 2.2"/>
+    <multiple_tree id="14" tree="45" lft="37" rgt="38" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="45" lft="39" rgt="40" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="43" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-append-to-exists-down.xml b/tests/data/test-append-to-exists-down.xml
index a742fe2..9f668c6 100644
--- a/tests/data/test-append-to-exists-down.xml
+++ b/tests/data/test-append-to-exists-down.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="23" rgt="28" depth="2" name="Node 3.2"/>
     <tree id="21" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="29" rgt="42" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="30" rgt="35" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="31" rgt="32" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="33" rgt="34" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="36" rgt="41" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="37" rgt="38" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="39" rgt="40" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="16" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="29" rgt="42" depth="2" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="30" rgt="35" depth="3" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="31" rgt="32" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="33" rgt="34" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="36" rgt="41" depth="3" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="37" rgt="38" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="39" rgt="40" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="16" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-append-to-exists-up.xml b/tests/data/test-append-to-exists-up.xml
index 6503342..1bb2c6b 100644
--- a/tests/data/test-append-to-exists-up.xml
+++ b/tests/data/test-append-to-exists-up.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="29" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="15" rgt="28" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="16" rgt="21" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="17" rgt="18" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="19" rgt="20" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="22" rgt="27" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="23" rgt="24" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="25" rgt="26" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="29" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="15" rgt="28" depth="2" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="16" rgt="21" depth="3" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="17" rgt="18" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="19" rgt="20" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="22" rgt="27" depth="3" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="23" rgt="24" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="25" rgt="26" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-append-to-new.xml b/tests/data/test-append-to-new.xml
index 805a689..1096870 100644
--- a/tests/data/test-append-to-new.xml
+++ b/tests/data/test-append-to-new.xml
@@ -23,71 +23,71 @@
     <tree id="21" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
     <tree id="23" lft="29" rgt="30" depth="2" name="New node"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="31" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="67" tree="23" lft="29" rgt="30" depth="2" name="New node"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="31" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="67" tree="23" lft="29" rgt="30" depth="2" name="New node"/>
 </dataset>
diff --git a/tests/data/test-children-multiple-roots-with-depth.php b/tests/data/test-children-multiple-tree-with-depth.php
similarity index 100%
rename from tests/data/test-children-multiple-roots-with-depth.php
rename to tests/data/test-children-multiple-tree-with-depth.php
diff --git a/tests/data/test-children-multiple-roots.php b/tests/data/test-children-multiple-tree.php
similarity index 100%
rename from tests/data/test-children-multiple-roots.php
rename to tests/data/test-children-multiple-tree.php
diff --git a/tests/data/test-delete-with-children.xml b/tests/data/test-delete-with-children.xml
index 36587a0..eaf516b 100644
--- a/tests/data/test-delete-with-children.xml
+++ b/tests/data/test-delete-with-children.xml
@@ -15,63 +15,63 @@
     <tree id="20" lft="23" rgt="28" depth="2" name="Node 3.2"/>
     <tree id="21" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="30" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="30" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-delete.xml b/tests/data/test-delete.xml
index 930abf3..f9c0241 100644
--- a/tests/data/test-delete.xml
+++ b/tests/data/test-delete.xml
@@ -21,69 +21,69 @@
     <tree id="20" lft="35" rgt="40" depth="2" name="Node 3.2"/>
     <tree id="21" lft="36" rgt="37" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="38" rgt="39" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="42" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="32" tree="23" lft="16" rgt="21" depth="1" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="17" rgt="18" depth="2" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="19" rgt="20" depth="2" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="22" rgt="27" depth="1" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="23" rgt="24" depth="2" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="25" rgt="26" depth="2" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="28" rgt="41" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="29" rgt="34" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="30" rgt="31" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="35" rgt="40" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="36" rgt="37" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="42" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="32" tree="23" lft="16" rgt="21" depth="1" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="17" rgt="18" depth="2" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="19" rgt="20" depth="2" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="22" rgt="27" depth="1" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="23" rgt="24" depth="2" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="25" rgt="26" depth="2" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="28" rgt="41" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="29" rgt="34" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="30" rgt="31" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="35" rgt="40" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="36" rgt="37" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-after-exists-another-tree.xml b/tests/data/test-insert-after-exists-another-tree.xml
index f71ae27..0c303ab 100644
--- a/tests/data/test-insert-after-exists-another-tree.xml
+++ b/tests/data/test-insert-after-exists-another-tree.xml
@@ -1,69 +1,69 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <dataset>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="45" lft="30" rgt="43" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="10" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="45" lft="30" rgt="43" depth="1" name="Updated node 2"/>
+    <multiple_tree id="10" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-after-exists-down.xml b/tests/data/test-insert-after-exists-down.xml
index 2f22dbe..8153a99 100644
--- a/tests/data/test-insert-after-exists-down.xml
+++ b/tests/data/test-insert-after-exists-down.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="23" rgt="28" depth="2" name="Node 3.2"/>
     <tree id="21" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="30" rgt="43" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="31" rgt="36" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="37" rgt="42" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="30" rgt="43" depth="1" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="31" rgt="36" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="37" rgt="42" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-after-exists-up.xml b/tests/data/test-insert-after-exists-up.xml
index 7ca1058..23cb621 100644
--- a/tests/data/test-insert-after-exists-up.xml
+++ b/tests/data/test-insert-after-exists-up.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-after-new.xml b/tests/data/test-insert-after-new.xml
index 70d2c5f..9030682 100644
--- a/tests/data/test-insert-after-new.xml
+++ b/tests/data/test-insert-after-new.xml
@@ -23,71 +23,71 @@
     <tree id="21" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
     <tree id="23" lft="30" rgt="31" depth="1" name="New node"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="67" tree="23" lft="30" rgt="31" depth="1" name="New node"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="67" tree="23" lft="30" rgt="31" depth="1" name="New node"/>
 </dataset>
diff --git a/tests/data/test-insert-before-exists-another-tree.xml b/tests/data/test-insert-before-exists-another-tree.xml
index e3f6d71..d128929 100644
--- a/tests/data/test-insert-before-exists-another-tree.xml
+++ b/tests/data/test-insert-before-exists-another-tree.xml
@@ -1,69 +1,69 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <dataset>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="45" lft="16" rgt="29" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="10" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="30" rgt="43" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="45" lft="16" rgt="29" depth="1" name="Updated node 2"/>
+    <multiple_tree id="10" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="30" rgt="43" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-before-exists-down.xml b/tests/data/test-insert-before-exists-down.xml
index 7ca1058..23cb621 100644
--- a/tests/data/test-insert-before-exists-down.xml
+++ b/tests/data/test-insert-before-exists-down.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-before-exists-up.xml b/tests/data/test-insert-before-exists-up.xml
index 8b99fb8..ce1d329 100644
--- a/tests/data/test-insert-before-exists-up.xml
+++ b/tests/data/test-insert-before-exists-up.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="16" rgt="29" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="17" rgt="22" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="18" rgt="19" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="20" rgt="21" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="23" rgt="28" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="24" rgt="25" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="26" rgt="27" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="2" rgt="15" depth="1" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="3" rgt="8" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="4" rgt="5" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="6" rgt="7" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="9" rgt="14" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="10" rgt="11" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="12" rgt="13" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="16" rgt="29" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="17" rgt="22" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="18" rgt="19" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="20" rgt="21" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="23" rgt="28" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="24" rgt="25" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="26" rgt="27" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="2" rgt="15" depth="1" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="3" rgt="8" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="4" rgt="5" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="6" rgt="7" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="9" rgt="14" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="10" rgt="11" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="12" rgt="13" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-insert-before-new.xml b/tests/data/test-insert-before-new.xml
index 31c8f96..5ec3d5b 100644
--- a/tests/data/test-insert-before-new.xml
+++ b/tests/data/test-insert-before-new.xml
@@ -23,71 +23,71 @@
     <tree id="21" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
     <tree id="23" lft="16" rgt="17" depth="1" name="New node"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="18" rgt="31" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="19" rgt="24" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="22" rgt="23" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="25" rgt="30" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="28" rgt="29" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="67" tree="23" lft="16" rgt="17" depth="1" name="New node"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="18" rgt="31" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="19" rgt="24" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="22" rgt="23" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="25" rgt="30" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="28" rgt="29" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="67" tree="23" lft="16" rgt="17" depth="1" name="New node"/>
 </dataset>
diff --git a/tests/data/test-leaves-multiple-roots-query.php b/tests/data/test-leaves-multiple-tree-query.php
similarity index 100%
rename from tests/data/test-leaves-multiple-roots-query.php
rename to tests/data/test-leaves-multiple-tree-query.php
diff --git a/tests/data/test-leaves-multiple-roots.php b/tests/data/test-leaves-multiple-tree.php
similarity index 100%
rename from tests/data/test-leaves-multiple-roots.php
rename to tests/data/test-leaves-multiple-tree.php
diff --git a/tests/data/test-make-root-exists.xml b/tests/data/test-make-root-exists.xml
index e94691a..9392990 100644
--- a/tests/data/test-make-root-exists.xml
+++ b/tests/data/test-make-root-exists.xml
@@ -1,69 +1,69 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <dataset>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="30" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="31" lft="1" rgt="14" depth="0" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="31" lft="2" rgt="7" depth="1" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="31" lft="3" rgt="4" depth="2" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="31" lft="5" rgt="6" depth="2" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="31" lft="8" rgt="13" depth="1" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="31" lft="9" rgt="10" depth="2" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="31" lft="11" rgt="12" depth="2" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="30" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="31" lft="1" rgt="14" depth="0" name="Updated node 2"/>
+    <multiple_tree id="32" tree="31" lft="2" rgt="7" depth="1" name="Node 2.1"/>
+    <multiple_tree id="33" tree="31" lft="3" rgt="4" depth="2" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="31" lft="5" rgt="6" depth="2" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="31" lft="8" rgt="13" depth="1" name="Node 2.2"/>
+    <multiple_tree id="36" tree="31" lft="9" rgt="10" depth="2" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="31" lft="11" rgt="12" depth="2" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-make-root-new.xml b/tests/data/test-make-root-new.xml
index 6f35171..20c0d31 100644
--- a/tests/data/test-make-root-new.xml
+++ b/tests/data/test-make-root-new.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <dataset>
     <tree id="1" lft="1" rgt="2" depth="0" name="Root"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="2" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="2" lft="1" rgt="2" depth="0" name="Root 2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="2" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="2" lft="1" rgt="2" depth="0" name="Root 2"/>
 </dataset>
diff --git a/tests/data/test-next-multiple-roots.php b/tests/data/test-next-multiple-tree.php
similarity index 100%
rename from tests/data/test-next-multiple-roots.php
rename to tests/data/test-next-multiple-tree.php
diff --git a/tests/data/test-parents-multiple-roots-with-depth.php b/tests/data/test-parents-multiple-tree-with-depth.php
similarity index 100%
rename from tests/data/test-parents-multiple-roots-with-depth.php
rename to tests/data/test-parents-multiple-tree-with-depth.php
diff --git a/tests/data/test-parents-multiple-roots.php b/tests/data/test-parents-multiple-tree.php
similarity index 100%
rename from tests/data/test-parents-multiple-roots.php
rename to tests/data/test-parents-multiple-tree.php
diff --git a/tests/data/test-prepend-to-exists-another-tree.xml b/tests/data/test-prepend-to-exists-another-tree.xml
index cbdd10e..b35e57f 100644
--- a/tests/data/test-prepend-to-exists-another-tree.xml
+++ b/tests/data/test-prepend-to-exists-another-tree.xml
@@ -1,69 +1,69 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <dataset>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="45" lft="17" rgt="30" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="10" tree="45" lft="18" rgt="23" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="45" lft="19" rgt="20" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="45" lft="21" rgt="22" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="45" lft="24" rgt="29" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="45" lft="25" rgt="26" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="45" lft="27" rgt="28" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="43" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="30" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="45" lft="17" rgt="30" depth="2" name="Updated node 2"/>
+    <multiple_tree id="10" tree="45" lft="18" rgt="23" depth="3" name="Node 2.1"/>
+    <multiple_tree id="11" tree="45" lft="19" rgt="20" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="45" lft="21" rgt="22" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="45" lft="24" rgt="29" depth="3" name="Node 2.2"/>
+    <multiple_tree id="14" tree="45" lft="25" rgt="26" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="45" lft="27" rgt="28" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="16" rgt="29" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="17" rgt="22" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="18" rgt="19" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="20" rgt="21" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="23" rgt="28" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="24" rgt="25" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="26" rgt="27" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="58" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="43" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="31" rgt="36" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="32" rgt="33" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="34" rgt="35" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="37" rgt="42" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="38" rgt="39" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="40" rgt="41" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="44" rgt="57" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="45" rgt="50" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="46" rgt="47" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="48" rgt="49" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="51" rgt="56" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="52" rgt="53" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="54" rgt="55" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-prepend-to-exists-down.xml b/tests/data/test-prepend-to-exists-down.xml
index c6d3a4d..424f5c7 100644
--- a/tests/data/test-prepend-to-exists-down.xml
+++ b/tests/data/test-prepend-to-exists-down.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="17" rgt="30" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="18" rgt="23" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="19" rgt="20" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="21" rgt="22" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="24" rgt="29" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="25" rgt="26" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="27" rgt="28" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="16" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="17" rgt="30" depth="2" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="18" rgt="23" depth="3" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="19" rgt="20" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="21" rgt="22" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="24" rgt="29" depth="3" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="25" rgt="26" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="27" rgt="28" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="16" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-prepend-to-exists-up.xml b/tests/data/test-prepend-to-exists-up.xml
index 35fbd32..3956535 100644
--- a/tests/data/test-prepend-to-exists-up.xml
+++ b/tests/data/test-prepend-to-exists-up.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="29" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="17" rgt="22" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="18" rgt="19" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="20" rgt="21" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="23" rgt="28" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="24" rgt="25" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="26" rgt="27" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="3" rgt="16" depth="2" name="Updated node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="4" rgt="9" depth="3" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="5" rgt="6" depth="4" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="7" rgt="8" depth="4" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="10" rgt="15" depth="3" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="11" rgt="12" depth="4" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="13" rgt="14" depth="4" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="29" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="17" rgt="22" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="18" rgt="19" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="20" rgt="21" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="23" rgt="28" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="24" rgt="25" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="26" rgt="27" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="3" rgt="16" depth="2" name="Updated node 2"/>
+    <multiple_tree id="32" tree="23" lft="4" rgt="9" depth="3" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="5" rgt="6" depth="4" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="7" rgt="8" depth="4" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="10" rgt="15" depth="3" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="11" rgt="12" depth="4" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="13" rgt="14" depth="4" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/data/test-prepend-to-new.xml b/tests/data/test-prepend-to-new.xml
index 19a052c..259c8c7 100644
--- a/tests/data/test-prepend-to-new.xml
+++ b/tests/data/test-prepend-to-new.xml
@@ -23,71 +23,71 @@
     <tree id="21" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
     <tree id="23" lft="17" rgt="18" depth="2" name="New node"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="31" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="19" rgt="24" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="22" rgt="23" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="25" rgt="30" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="28" rgt="29" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="67" tree="23" lft="17" rgt="18" depth="2" name="New node"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="46" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="31" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="19" rgt="24" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="22" rgt="23" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="25" rgt="30" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="28" rgt="29" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="32" rgt="45" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="33" rgt="38" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="36" rgt="37" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="39" rgt="44" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="42" rgt="43" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="67" tree="23" lft="17" rgt="18" depth="2" name="New node"/>
 </dataset>
diff --git a/tests/data/test-prev-multiple-roots.php b/tests/data/test-prev-multiple-tree.php
similarity index 100%
rename from tests/data/test-prev-multiple-roots.php
rename to tests/data/test-prev-multiple-tree.php
diff --git a/tests/data/test-roots-multiple-roots-query.php b/tests/data/test-roots-multiple-tree-query.php
similarity index 100%
rename from tests/data/test-roots-multiple-roots-query.php
rename to tests/data/test-roots-multiple-tree-query.php
diff --git a/tests/data/test.xml b/tests/data/test.xml
index c94536f..a2f0c73 100644
--- a/tests/data/test.xml
+++ b/tests/data/test.xml
@@ -22,70 +22,70 @@
     <tree id="20" lft="37" rgt="42" depth="2" name="Node 3.2"/>
     <tree id="21" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
     <tree id="22" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
-    <multiple_roots_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
-    <multiple_roots_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
-    <multiple_roots_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
-    <multiple_roots_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
-    <multiple_roots_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
-    <multiple_roots_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
-    <multiple_roots_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
-    <multiple_roots_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
-    <multiple_roots_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
-    <multiple_roots_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
-    <multiple_roots_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
-    <multiple_roots_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
-    <multiple_roots_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
-    <multiple_roots_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
-    <multiple_roots_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
-    <multiple_roots_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
-    <multiple_roots_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
-    <multiple_roots_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
-    <multiple_roots_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
-    <multiple_roots_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
-    <multiple_roots_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
-    <multiple_roots_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
-    <multiple_roots_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
-    <multiple_roots_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="1" tree="1" lft="1" rgt="44" depth="0" name="Root 1"/>
+    <multiple_tree id="2" tree="1" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="3" tree="1" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="4" tree="1" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="5" tree="1" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="6" tree="1" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="7" tree="1" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="8" tree="1" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="9" tree="1" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="10" tree="1" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="11" tree="1" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="12" tree="1" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="13" tree="1" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="14" tree="1" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="15" tree="1" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="16" tree="1" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="17" tree="1" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="18" tree="1" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="19" tree="1" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="20" tree="1" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="21" tree="1" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="22" tree="1" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="23" tree="23" lft="1" rgt="44" depth="0" name="Root 2"/>
+    <multiple_tree id="24" tree="23" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="25" tree="23" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="26" tree="23" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="27" tree="23" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="28" tree="23" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="29" tree="23" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="30" tree="23" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="31" tree="23" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="32" tree="23" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="33" tree="23" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="34" tree="23" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="35" tree="23" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="36" tree="23" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="37" tree="23" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="38" tree="23" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="39" tree="23" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="40" tree="23" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="41" tree="23" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="42" tree="23" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="43" tree="23" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="44" tree="23" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
+    <multiple_tree id="45" tree="45" lft="1" rgt="44" depth="0" name="Root 3"/>
+    <multiple_tree id="46" tree="45" lft="2" rgt="15" depth="1" name="Node 1"/>
+    <multiple_tree id="47" tree="45" lft="3" rgt="8" depth="2" name="Node 1.1"/>
+    <multiple_tree id="48" tree="45" lft="4" rgt="5" depth="3" name="Node 1.1.1"/>
+    <multiple_tree id="49" tree="45" lft="6" rgt="7" depth="3" name="Node 1.1.2"/>
+    <multiple_tree id="50" tree="45" lft="9" rgt="14" depth="2" name="Node 1.2"/>
+    <multiple_tree id="51" tree="45" lft="10" rgt="11" depth="3" name="Node 1.2.1"/>
+    <multiple_tree id="52" tree="45" lft="12" rgt="13" depth="3" name="Node 1.2.2"/>
+    <multiple_tree id="53" tree="45" lft="16" rgt="29" depth="1" name="Node 2"/>
+    <multiple_tree id="54" tree="45" lft="17" rgt="22" depth="2" name="Node 2.1"/>
+    <multiple_tree id="55" tree="45" lft="18" rgt="19" depth="3" name="Node 2.1.1"/>
+    <multiple_tree id="56" tree="45" lft="20" rgt="21" depth="3" name="Node 2.1.2"/>
+    <multiple_tree id="57" tree="45" lft="23" rgt="28" depth="2" name="Node 2.2"/>
+    <multiple_tree id="58" tree="45" lft="24" rgt="25" depth="3" name="Node 2.2.1"/>
+    <multiple_tree id="59" tree="45" lft="26" rgt="27" depth="3" name="Node 2.2.2"/>
+    <multiple_tree id="60" tree="45" lft="30" rgt="43" depth="1" name="Node 3"/>
+    <multiple_tree id="61" tree="45" lft="31" rgt="36" depth="2" name="Node 3.1"/>
+    <multiple_tree id="62" tree="45" lft="32" rgt="33" depth="3" name="Node 3.1.1"/>
+    <multiple_tree id="63" tree="45" lft="34" rgt="35" depth="3" name="Node 3.1.2"/>
+    <multiple_tree id="64" tree="45" lft="37" rgt="42" depth="2" name="Node 3.2"/>
+    <multiple_tree id="65" tree="45" lft="38" rgt="39" depth="3" name="Node 3.2.1"/>
+    <multiple_tree id="66" tree="45" lft="40" rgt="41" depth="3" name="Node 3.2.2"/>
 </dataset>
diff --git a/tests/migrations/mysql.sql b/tests/migrations/mysql.sql
index 8c3facc..e8d861a 100644
--- a/tests/migrations/mysql.sql
+++ b/tests/migrations/mysql.sql
@@ -12,9 +12,9 @@ CREATE TABLE `tree` (
   `name`  VARCHAR(255) NOT NULL
 );
 
-DROP TABLE IF EXISTS `multiple_roots_tree`;
+DROP TABLE IF EXISTS `multiple_tree`;
 
-CREATE TABLE `multiple_roots_tree` (
+CREATE TABLE `multiple_tree` (
   `id`    INT(11)      NOT NULL PRIMARY KEY AUTO_INCREMENT,
   `tree`  INT(11),
   `lft`   INT(11)      NOT NULL,
diff --git a/tests/migrations/sqlite.sql b/tests/migrations/sqlite.sql
index f8aae3f..a4408ae 100644
--- a/tests/migrations/sqlite.sql
+++ b/tests/migrations/sqlite.sql
@@ -12,9 +12,9 @@ CREATE TABLE "tree" (
   "name"  TEXT    NOT NULL
 );
 
-DROP TABLE IF EXISTS "multiple_roots_tree";
+DROP TABLE IF EXISTS "multiple_tree";
 
-CREATE TABLE "multiple_roots_tree" (
+CREATE TABLE "multiple_tree" (
   "id"    INTEGER NOT NULL PRIMARY KEY,
   "tree"  INTEGER,
   "lft"   INTEGER NOT NULL,
diff --git a/tests/models/MultipleRootsTree.php b/tests/models/MultipleTree.php
similarity index 86%
rename from tests/models/MultipleRootsTree.php
rename to tests/models/MultipleTree.php
index 8710c18..bfa140e 100644
--- a/tests/models/MultipleRootsTree.php
+++ b/tests/models/MultipleTree.php
@@ -10,7 +10,7 @@ namespace tests\models;
 use creocoder\nestedsets\NestedSetsBehavior;
 
 /**
- * MultipleRootsTree
+ * MultipleTree
  *
  * @property integer $id
  * @property integer $tree
@@ -19,14 +19,14 @@ use creocoder\nestedsets\NestedSetsBehavior;
  * @property integer $depth
  * @property string $name
  */
-class MultipleRootsTree extends \yii\db\ActiveRecord
+class MultipleTree extends \yii\db\ActiveRecord
 {
     /**
      * @inheritdoc
      */
     public static function tableName()
     {
-        return 'multiple_roots_tree';
+        return 'multiple_tree';
     }
 
     /**
@@ -67,6 +67,6 @@ class MultipleRootsTree extends \yii\db\ActiveRecord
      */
     public static function find()
     {
-        return new MultipleRootsTreeQuery(get_called_class());
+        return new MultipleTreeQuery(get_called_class());
     }
 }
diff --git a/tests/models/MultipleRootsTreeQuery.php b/tests/models/MultipleTreeQuery.php
similarity index 83%
rename from tests/models/MultipleRootsTreeQuery.php
rename to tests/models/MultipleTreeQuery.php
index 9ed2a89..4137cbc 100644
--- a/tests/models/MultipleRootsTreeQuery.php
+++ b/tests/models/MultipleTreeQuery.php
@@ -10,9 +10,9 @@ namespace tests\models;
 use creocoder\nestedsets\NestedSetsQueryBehavior;
 
 /**
- * MultipleRootsTreeQuery
+ * MultipleTreeQuery
  */
-class MultipleRootsTreeQuery extends \yii\db\ActiveQuery
+class MultipleTreeQuery extends \yii\db\ActiveQuery
 {
     /**
      * @inheritdoc