Using COLLATE inside Doctrine DQL Query (Symfony2)

Question

I can\'t find anything related to using COLLATE in a DQL query with Doctrine (and ofcourse it doesn\'t seem to work).

My specific problem:

I have a table wit

Answer 1

Following Cerad 's suggestion to write a custom DQL function: http://www.doctrine-project.org/2010/03/29/doctrine2-custom-dql-udfs.html

I managed to create this:

namespace MyCompany\MyBundle\DQL;

use Doctrine\ORM\Query\AST\Functions\FunctionNode;
use Doctrine\ORM\Query\Lexer;

class CollateFunction extends FunctionNode
{
    public $expressionToCollate = null;
    public $collation = null;

    public function parse(\Doctrine\ORM\Query\Parser $parser)
    {
        $parser->match(Lexer::T_IDENTIFIER);
        $parser->match(Lexer::T_OPEN_PARENTHESIS);
        $this->expressionToCollate = $parser->StringPrimary();

        $parser->match(Lexer::T_COMMA);

        $parser->match(Lexer::T_IDENTIFIER);
        $lexer = $parser->getLexer();
        $this->collation = $lexer->token['value'];

        $parser->match(Lexer::T_CLOSE_PARENTHESIS);
    }

    public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
    {
        return sprintf( '%s COLLATE %s', $this->expressionToCollate->dispatch($sqlWalker), $this->collation );
    }
}

When registered to the config.yml (http://symfony.com/doc/current/cookbook/doctrine/custom_dql_functions.html) This will look for a Collate 'function' with two arguments: a field and a charset (no valid charset detection yet).

Works like (written in DQL)

COLLATE( field , collation ) 

And creates (in runable MySQL)

`field` COLLATE collation 

Ofcourse collation should be a valid charset (such as utf8_bin) or you will get a MySQL error.

I guess there is a simpler solution, but I only could create this as a 'function'. At least the problem is solved.