diff --git a/lib/private/db/statementwrapper.php b/lib/private/db/statementwrapper.php
index a85c0167e0..2f833a27a6 100644
--- a/lib/private/db/statementwrapper.php
+++ b/lib/private/db/statementwrapper.php
@@ -69,6 +69,7 @@ class OC_DB_StatementWrapper {
 			return false;
 		}
 		if ($this->isManipulation) {
+			$this->statement->closeCursor();
 			return $this->statement->rowCount();
 		} else {
 			return $this;
diff --git a/lib/public/appframework/db/mapper.php b/lib/public/appframework/db/mapper.php
index 03f0fe3aa7..fd3dc9b747 100644
--- a/lib/public/appframework/db/mapper.php
+++ b/lib/public/appframework/db/mapper.php
@@ -41,7 +41,7 @@ abstract class Mapper {
 
 	/**
 	 * @param IDb $db Instance of the Db abstraction layer
-	 * @param string $tableName the name of the table. set this to allow entity 
+	 * @param string $tableName the name of the table. set this to allow entity
 	 * @param string $entityClass the name of the entity that the sql should be
 	 * mapped to queries without using sql
 	 */
@@ -70,10 +70,12 @@ abstract class Mapper {
 	/**
 	 * Deletes an entity from the table
 	 * @param Entity $entity the entity that should be deleted
+	 * @return Entity the deleted entity
 	 */
 	public function delete(Entity $entity){
 		$sql = 'DELETE FROM `' . $this->tableName . '` WHERE `id` = ?';
-		$this->execute($sql, array($entity->getId()));
+		$this->execute($sql, [$entity->getId()]);
+		return $entity;
 	}
 
 
@@ -88,14 +90,14 @@ abstract class Mapper {
 		$properties = $entity->getUpdatedFields();
 		$values = '';
 		$columns = '';
-		$params = array();
+		$params = [];
 
 		// build the fields
 		$i = 0;
 		foreach($properties as $property => $updated) {
 			$column = $entity->propertyToColumn($property);
 			$getter = 'get' . ucfirst($property);
-			
+
 			$columns .= '`' . $column . '`';
 			$values .= '?';
 
@@ -112,10 +114,11 @@ abstract class Mapper {
 
 		$sql = 'INSERT INTO `' . $this->tableName . '`(' .
 				$columns . ') VALUES(' . $values . ')';
-		
+
 		$this->execute($sql, $params);
 
 		$entity->setId((int) $this->db->getInsertId($this->tableName));
+
 		return $entity;
 	}
 
@@ -147,7 +150,7 @@ abstract class Mapper {
 		unset($properties['id']);
 
 		$columns = '';
-		$params = array();
+		$params = [];
 
 		// build the fields
 		$i = 0;
@@ -155,7 +158,7 @@ abstract class Mapper {
 
 			$column = $entity->propertyToColumn($property);
 			$getter = 'get' . ucfirst($property);
-			
+
 			$columns .= '`' . $column . '` = ?';
 
 			// only append colon if there are more entries
@@ -167,7 +170,7 @@ abstract class Mapper {
 			$i++;
 		}
 
-		$sql = 'UPDATE `' . $this->tableName . '` SET ' . 
+		$sql = 'UPDATE `' . $this->tableName . '` SET ' .
 				$columns . ' WHERE `id` = ?';
 		array_push($params, $id);
 
@@ -185,7 +188,7 @@ abstract class Mapper {
 	 * @param int $offset from which row we want to start
 	 * @return \PDOStatement the database query result
 	 */
-	protected function execute($sql, array $params=array(), $limit=null, $offset=null){
+	protected function execute($sql, array $params=[], $limit=null, $offset=null){
 		$query = $this->db->prepareQuery($sql, $limit, $offset);
 
 		$index = 1;  // bindParam is 1 indexed
@@ -199,12 +202,12 @@ abstract class Mapper {
 				case 'boolean':
 					$pdoConstant = \PDO::PARAM_BOOL;
 					break;
-				
+
 				default:
 					$pdoConstant = \PDO::PARAM_STR;
 					break;
 			}
-			
+
 			$query->bindValue($index, $param, $pdoConstant);
 
 			$index++;
@@ -226,14 +229,16 @@ abstract class Mapper {
 	 * @throws MultipleObjectsReturnedException if more than one item exist
 	 * @return array the result as row
 	 */
-	protected function findOneQuery($sql, array $params=array(), $limit=null, $offset=null){
-		$result = $this->execute($sql, $params, $limit, $offset);
-		$row = $result->fetch();
+	protected function findOneQuery($sql, array $params=[], $limit=null, $offset=null){
+		$stmt = $this->execute($sql, $params, $limit, $offset);
+		$row = $stmt->fetch();
 
 		if($row === false || $row === null){
+			$stmt->closeCursor();
 			throw new DoesNotExistException('No matching entry found');
 		}
-		$row2 = $result->fetch();
+		$row2 = $stmt->fetch();
+		$stmt->closeCursor();
 		//MDB2 returns null, PDO and doctrine false when no row is available
 		if( ! ($row2 === false || $row2 === null )) {
 			throw new MultipleObjectsReturnedException('More than one result');
@@ -262,15 +267,17 @@ abstract class Mapper {
 	 * @param int $offset from which row we want to start
 	 * @return array all fetched entities
 	 */
-	protected function findEntities($sql, array $params=array(), $limit=null, $offset=null) {
-		$result = $this->execute($sql, $params, $limit, $offset);
+	protected function findEntities($sql, array $params=[], $limit=null, $offset=null) {
+		$stmt = $this->execute($sql, $params, $limit, $offset);
 
-		$entities = array();
-		
-		while($row = $result->fetch()){
+		$entities = [];
+
+		while($row = $stmt->fetch()){
 			$entities[] = $this->mapRowToEntity($row);
 		}
 
+		$stmt->closeCursor();
+
 		return $entities;
 	}
 
@@ -286,7 +293,7 @@ abstract class Mapper {
 	 * @throws MultipleObjectsReturnedException if more than one item exist
 	 * @return Entity the entity
 	 */
-	protected function findEntity($sql, array $params=array(), $limit=null, $offset=null){
+	protected function findEntity($sql, array $params=[], $limit=null, $offset=null){
 		return $this->mapRowToEntity($this->findOneQuery($sql, $params, $limit, $offset));
 	}
 
diff --git a/tests/lib/appframework/db/mappertest.php b/tests/lib/appframework/db/mappertest.php
index 6ad8cd86bf..9cbc01883e 100644
--- a/tests/lib/appframework/db/mappertest.php
+++ b/tests/lib/appframework/db/mappertest.php
@@ -74,7 +74,7 @@ class MapperTest extends MapperTestUtility {
 		$rows = array(
 			array('hi')
 		);
-		$this->setMapperResult($sql, $params, $rows);		
+		$this->setMapperResult($sql, $params, $rows);
 		$this->mapper->find($sql, $params);
 	}
 
@@ -84,7 +84,7 @@ class MapperTest extends MapperTestUtility {
 		$rows = array(
 			array('pre_name' => 'hi')
 		);
-		$this->setMapperResult($sql, $params, $rows);
+		$this->setMapperResult($sql, $params, $rows, null, null, true);
 		$this->mapper->findOneEntity($sql, $params);
 	}
 
@@ -92,7 +92,7 @@ class MapperTest extends MapperTestUtility {
 		$sql = 'hi';
 		$params = array('jo');
 		$rows = array();
-		$this->setMapperResult($sql, $params, $rows);		
+		$this->setMapperResult($sql, $params, $rows);
 		$this->setExpectedException(
 			'\OCP\AppFramework\Db\DoesNotExistException');
 		$this->mapper->find($sql, $params);
@@ -102,7 +102,7 @@ class MapperTest extends MapperTestUtility {
 		$sql = 'hi';
 		$params = array('jo');
 		$rows = array();
-		$this->setMapperResult($sql, $params, $rows);
+		$this->setMapperResult($sql, $params, $rows, null, null, true);
 		$this->setExpectedException(
 			'\OCP\AppFramework\Db\DoesNotExistException');
 		$this->mapper->findOneEntity($sql, $params);
@@ -114,7 +114,7 @@ class MapperTest extends MapperTestUtility {
 		$rows = array(
 			array('jo'), array('ho')
 		);
-		$this->setMapperResult($sql, $params, $rows);
+		$this->setMapperResult($sql, $params, $rows, null, null, true);
 		$this->setExpectedException(
 			'\OCP\AppFramework\Db\MultipleObjectsReturnedException');
 		$this->mapper->find($sql, $params);
@@ -126,7 +126,7 @@ class MapperTest extends MapperTestUtility {
 		$rows = array(
 			array('jo'), array('ho')
 		);
-		$this->setMapperResult($sql, $params, $rows);
+		$this->setMapperResult($sql, $params, $rows, null, null, true);
 		$this->setExpectedException(
 			'\OCP\AppFramework\Db\MultipleObjectsReturnedException');
 		$this->mapper->findOneEntity($sql, $params);
@@ -249,7 +249,7 @@ class MapperTest extends MapperTestUtility {
 		$entity = new Example();
 		$entity->setPreName('hi');
 		$entity->resetUpdatedFields();
-		$this->setMapperResult($sql, array(), $rows);
+		$this->setMapperResult($sql, array(), $rows, null, null, true);
 		$result = $this->mapper->findAllEntities($sql);
 		$this->assertEquals(array($entity), $result);
 	}
diff --git a/tests/lib/appframework/db/mappertestutility.php b/tests/lib/appframework/db/mappertestutility.php
index ad7a67a96b..0053b2c682 100644
--- a/tests/lib/appframework/db/mappertestutility.php
+++ b/tests/lib/appframework/db/mappertestutility.php
@@ -36,7 +36,7 @@ abstract class MapperTestUtility extends \Test\TestCase {
 	private $prepareAt;
 	private $fetchAt;
 	private $iterators;
-	
+
 
 	/**
 	 * Run this function before the actual test to either set or initialize the
@@ -51,7 +51,7 @@ abstract class MapperTestUtility extends \Test\TestCase {
 			->getMock();
 
 		$this->query = $this->getMock('Query', array('execute', 'bindValue'));
-		$this->pdoResult = $this->getMock('Result', array('fetch'));
+		$this->pdoResult = $this->getMock('Result', array('fetch', 'closeCursor'));
 		$this->queryAt = 0;
 		$this->prepareAt = 0;
 		$this->iterators = array();
@@ -69,7 +69,7 @@ abstract class MapperTestUtility extends \Test\TestCase {
 	 * will be called on the result
 	 */
 	protected function setMapperResult($sql, $arguments=array(), $returnRows=array(),
-		$limit=null, $offset=null){
+		$limit=null, $offset=null, $expectClose=false){
 
 		$this->iterators[] = new ArgumentIterator($returnRows);
 
@@ -88,8 +88,14 @@ abstract class MapperTestUtility extends \Test\TestCase {
 					}
 
 					return $result;
-			  	}
+				}
 			));
+		if ($expectClose) {
+			$closing = $this->once();
+		} else {
+			$closing = $this->any();
+		}
+		$this->pdoResult->expects($closing)->method('closeCursor');
 
 		$index = 1;
 		foreach($arguments as $argument) {
@@ -105,7 +111,7 @@ abstract class MapperTestUtility extends \Test\TestCase {
 				case 'boolean':
 					$pdoConstant = \PDO::PARAM_BOOL;
 					break;
-				
+
 				default:
 					$pdoConstant = \PDO::PARAM_STR;
 					break;
@@ -138,14 +144,14 @@ abstract class MapperTestUtility extends \Test\TestCase {
 		} elseif($limit === null && $offset !== null) {
 			$this->db->expects($this->at($this->prepareAt))
 				->method('prepareQuery')
-				->with($this->equalTo($sql), 
+				->with($this->equalTo($sql),
 					$this->equalTo(null),
 					$this->equalTo($offset))
 				->will(($this->returnValue($this->query)));
 		} else  {
 			$this->db->expects($this->at($this->prepareAt))
 				->method('prepareQuery')
-				->with($this->equalTo($sql), 
+				->with($this->equalTo($sql),
 					$this->equalTo($limit),
 					$this->equalTo($offset))
 				->will(($this->returnValue($this->query)));
@@ -162,11 +168,11 @@ abstract class MapperTestUtility extends \Test\TestCase {
 class ArgumentIterator {
 
 	private $arguments;
-	
+
 	public function __construct($arguments){
 		$this->arguments = $arguments;
 	}
-	
+
 	public function next(){
 		$result = array_shift($this->arguments);
 		if($result === null){