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phpdoctrine-ormdoctrine-query

Doctrine order by compound expression


I want to replicate the following query which sorts all users by name, but those whose names start with Z come first:

SELECT *
FROM user
ORDER BY LEFT(name, 1) != 'Z', name

I have this:

$qb = $this->getEntityManager()->createQueryBuilder();
$qb->select('u')
    ->addSelect($qb->expr()->neq($qb->expr()->substring('u.name', 1, 1), $qb->expr()->literal('Z')) . ' AS HIDDEN firstLetterIsNotZ')
    ->from(user::class, 'u')
    ->orderBy('firstLetterIsNotZ')
    ->addOrderBy('u.name');

The generated DQL looks sane enough:

SELECT s, SUBSTRING(u.name, 1, 1) <> 'Z' AS HIDDEN descriptionFirstLetter
FROM user u
ORDER BY firstLetterIsNotZASC, s.description ASC

But the lexer does not like it: Error: Expected Doctrine\ORM\Query\Lexer::T_FROM, got '<'


Solution

  • Doctrine does not handle conditions well inside of the select statement.

    You can circumvent the issue by wrapping your condition with a CASE WHEN to produce your desired result.

    I've also parameterized the letter condition to allow it to be more portable, in case you wish to add it as dynamic value.

    $em = $this->getEntityManager();
    $expr = $em->getExpressionBuilder();
    $q = $em->createQueryBuilder()
        ->select('u')
        ->addSelect('(CASE WHEN ' . $expr->neq($expr->substring('u.name', 1, 1), ':letter') . ' THEN 0 ELSE 1 END) AS HIDDEN firstLetterIsNotZ')
        ->from(user::class, 'u')
        ->orderBy('firstLetterIsNotZ')
        ->addOrderBy('u.name')
        ->setParameter('letter', 'Z')
        ->getQuery();
    
    dump($q->getDQL());
    dump($q->getResult());
    

    Resulting DQL

    SELECT u, (CASE WHEN SUBSTRING(u.name, 1, 1) <> :letter THEN 1 ELSE 0 END) AS HIDDEN firstLetterIsNotZ 
    FROM user u 
    ORDER BY firstLetterIsNotZ ASC, u.name ASC
    

    Resulting Data: (firstLetterIsNotZ not HIDDEN)

    array:3 [▼
      0 => array:2 [▼
        0 => User {#2163 ▶}
        "firstLetterIsNotZ" => "0"
      ]
      1 => array:2 [▼
        0 => User {#2167 ▶}
        "firstLetterIsNotZ" => "1"
      ]
      2 => array:2 [▼
        0 => User {#2168 ▶}
        "firstLetterIsNotZ" => "1"
      ]
    ]