diff --git a/tests/DatabaseTestTrait.php b/tests/DatabaseTestTrait.php
index 7d255c693b..eae5ce2ac9 100644
--- a/tests/DatabaseTestTrait.php
+++ b/tests/DatabaseTestTrait.php
@@ -34,6 +34,8 @@ trait DatabaseTestTrait
 		StaticDatabase::statConnect($_SERVER);
 		// Rollbacks every DB usage (in case the test couldn't call tearDown)
 		StaticDatabase::statRollback();
+		// Rollback the first, outer transaction just 2 be sure
+		StaticDatabase::getGlobConnection()->rollBack();
 		// Start the first, outer transaction
 		StaticDatabase::getGlobConnection()->beginTransaction();
 	}
diff --git a/tests/Util/Database/ExtendedPDO.php b/tests/Util/Database/ExtendedPDO.php
index 6a59d2aeec..c9ce42b3ee 100644
--- a/tests/Util/Database/ExtendedPDO.php
+++ b/tests/Util/Database/ExtendedPDO.php
@@ -69,7 +69,7 @@ class ExtendedPDO extends PDO
 	{
 		if($this->_transactionDepth <= 0 || !$this->hasSavepoint()) {
 			parent::beginTransaction();
-			$this->_transactionDepth = $this->_transactionDepth < 0 ? 0 : $this->_transactionDepth;
+			$this->_transactionDepth = 0;
 		} else {
 			$this->exec("SAVEPOINT LEVEL{$this->_transactionDepth}");
 		}
@@ -84,14 +84,15 @@ class ExtendedPDO extends PDO
 	 */
 	public function commit()
 	{
+		// We don't want to "really" commit something, so skip the most outer hierarchy
+		if ($this->_transactionDepth <= 1 && $this->hasSavepoint()) {
+			$this->_transactionDepth = $this->_transactionDepth <= 0 ? 0 : 1;
+			return true;
+		}
+
 		$this->_transactionDepth--;
 
-		if($this->_transactionDepth <= 0 || !$this->hasSavepoint()) {
-			parent::commit();
-			$this->_transactionDepth = $this->_transactionDepth < 0 ? 0 : $this->_transactionDepth;
-		} else {
-			$this->exec("RELEASE SAVEPOINT LEVEL{$this->_transactionDepth}");
-		}
+		$this->exec("RELEASE SAVEPOINT LEVEL{$this->_transactionDepth}");
 	}
 
 	/**
@@ -102,14 +103,15 @@ class ExtendedPDO extends PDO
 	 */
 	public function rollBack()
 	{
-		if ($this->_transactionDepth <= 0) {
-			throw new PDOException('Rollback error : There is no transaction started');
-		}
-
 		$this->_transactionDepth--;
 
-		if($this->_transactionDepth == 0 || !$this->hasSavepoint()) {
-			parent::rollBack();
+		if($this->_transactionDepth <= 0 || !$this->hasSavepoint()) {
+			$this->_transactionDepth = 0;
+			try {
+				parent::rollBack();
+			} catch (PDOException $e) {
+				// this shouldn't happen, but it does ...
+			}
 		} else {
 			$this->exec("ROLLBACK TO SAVEPOINT LEVEL{$this->_transactionDepth}");
 		}
diff --git a/tests/Util/Database/StaticDatabase.php b/tests/Util/Database/StaticDatabase.php
index 48b3929788..3bf6396a94 100644
--- a/tests/Util/Database/StaticDatabase.php
+++ b/tests/Util/Database/StaticDatabase.php
@@ -39,6 +39,9 @@ class StaticDatabase extends Database
 	 */
 	private static $staticConnection;
 
+	/** @var bool  */
+	private $_locked = false;
+
 	/**
 	 * Override the behaviour of connect, due there is just one, static connection at all
 	 *
@@ -77,6 +80,31 @@ class StaticDatabase extends Database
 		return true;
 	}
 
+	/** Mock for locking tables */
+	public function lock($table)
+	{
+		if ($this->_locked) {
+			return false;
+		}
+
+		$this->in_transaction = true;
+		$this->_locked = true;
+
+		return true;
+	}
+
+	/** Mock for unlocking tables */
+	public function unlock()
+	{
+		// See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
+		$this->performCommit();
+
+		$this->in_transaction = false;
+		$this->_locked = false;
+
+		return true;
+	}
+
 	/**
 	 * Does a commit
 	 *
@@ -163,18 +191,6 @@ class StaticDatabase extends Database
 		return self::$staticConnection;
 	}
 
-	/**
-	 * Perform a global commit for every nested transaction of the static connection
-	 */
-	public static function statCommit()
-	{
-		if (isset(self::$staticConnection)) {
-			while (self::$staticConnection->getTransactionDepth() > 0) {
-				self::$staticConnection->commit();
-			}
-		}
-	}
-
 	/**
 	 * Perform a global rollback for every nested transaction of the static connection
 	 */