Use this to write a user defined dql function then use it.
<?php
class DateDiff extends FunctionNode
{
// (1)
public $firstDateExpression = null;
public $secondDateExpression = null;
public function parse(\Doctrine\ORM\Query\Parser $parser)
{
$parser->match(Lexer::T_IDENTIFIER); // (2)
$parser->match(Lexer::T_OPEN_PARENTHESIS); // (3)
$this->firstDateExpression = $parser->ArithmeticPrimary(); // (4)
$parser->match(Lexer::T_COMMA); // (5)
$this->secondDateExpression = $parser->ArithmeticPrimary(); // (6)
$parser->match(Lexer::T_CLOSE_PARENTHESIS); // (3)
}
public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
{
return 'DATEDIFF(' .
$this->firstDateExpression->dispatch($sqlWalker) . ', ' .
$this->secondDateExpression->dispatch($sqlWalker) .
')'; // (7)
}
}