Conversione di MySQL in Doctrine Query Builder. Problemi con IF e CONCAT. O un altro approccio per le sottoquery su select

Ok ho trovato la soluzione.

Puoi usare CASE invece di IF . Dai un'occhiata, ma quando utilizzo CASE Non riesco a CONCAT i miei campi:

$em = $this->getDoctrine()->getEntityManager();
$qb = $em->createQueryBuilder();
$q = $qb
      ->select("c.id")
      ->addSelect("CASE WHEN (c.parent IS NULL) THEN c.name ELSE 'something' END")
      ->from("MyBundle:Category", "c")
      ->leftJoin("c.parent", "t");

echo $q->getQuery()->getSQL();

Un'altra soluzione è creare la tua funzione DQL, come IF e usalo in questo modo:

$em = $this->getDoctrine()->getEntityManager();
$qb = $em->createQueryBuilder();
$q = $qb
      ->select("c.id")
      ->addSelect("IF(c.parent IS NULL, c.name, CONCAT(CONCAT(t.name, ' / '), c.name))")
      ->from("MyBundle:Category", "c")
      ->leftJoin("c.parent", "t");

echo $q->getQuery()->getSQL();

Per creare questo SE puoi andare a questo link e imparare:http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/ dql-doctrine-query-language.html#add-your-own functions-to-the-dql-language

Pubblicherò qui la mia classe per questo IF e config.yml per aiutare altre persone. Ecco la classe IfFunction (l'ho presa da https://github.com/beberlei/DoctrineExtensions/blob/master/src/Query/Mysql/IfElse.php ):

<?php
namespace MyName\MiscBundle\Doctrine\ORM\Query\AST\Functions;

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

/**
 * Usage: IF(expr1, expr2, expr3)
 * 
 * If expr1 is TRUE (expr1 <> 0 and expr1 <> NULL) then IF() returns expr2;
 * otherwise it returns expr3. IF() returns a numeric or string value,
 * depending on the context in which it is used. 
 * 
 * @author  Andrew Mackrodt <[email protected]>
 * @version 2011.06.19
 */
class IfFunction extends FunctionNode
{
    private $expr = array();

    public function parse(\Doctrine\ORM\Query\Parser $parser)
    {
        $parser->match(Lexer::T_IDENTIFIER);
        $parser->match(Lexer::T_OPEN_PARENTHESIS);
        $this->expr[] = $parser->ConditionalExpression();

        for ($i = 0; $i < 2; $i++)
        {
            $parser->match(Lexer::T_COMMA);
            $this->expr[] = $parser->ArithmeticExpression();
        }

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

    public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
    {
        return sprintf('IF(%s, %s, %s)',
            $sqlWalker->walkConditionalExpression($this->expr[0]),
            $sqlWalker->walkArithmeticPrimary($this->expr[1]),
            $sqlWalker->walkArithmeticPrimary($this->expr[2]));
    }
}

Dopodiché devi aggiornare il tuo config.yml in questo modo (ho appena aggiunto le ultime 3 righe):

doctrine:
    dbal:
        driver:   "%database_driver%"
        host:     "%database_host%"
        port:     "%database_port%"
        dbname:   "%database_name%"
        user:     "%database_user%"
        password: "%database_password%"
        charset:  UTF8

    orm:
        auto_generate_proxy_classes: "%kernel.debug%"
        auto_mapping: true
        dql: #ADDED THIS LINE
            string_functions: #ADDED THIS LINE
                IF: MyName\MiscBundle\Doctrine\ORM\Query\AST\Functions\IfFunction #ADDED THIS LINE

Grazie