public function getQueryBuilderMock($connection)
{
$exprmock = $this->getMock('Doctrine\\DBAL\\Query\\Expression\\ExpressionBuilder', null, [$connection]);
$mock = $this->getMock("Doctrine\\DBAL\\Query\\QueryBuilder", ['expr'], [$connection]);
$mock->expects($this->any())->method('expr')->will($this->returnValue($exprmock));
return $mock;
}