在MySQL中不使用GROUP获取"#1111 - 无效使用组功能"

Question

    $qb = $this->createQueryBuilder('t');

    return $qb
        ->join('t.customers', 'c')
        ->where($qb->expr()->eq('t.user', $user->getId()))
        ->andWhere($qb->expr()->gt($qb->expr()->count('c'), 0))
        ->orderBy('t.name')->getQuery()->getResult();

上面的查询(Doctrine2生成一个)给了我这个错误:

#1111 - Invalid use of group function

但奇怪的是我没有使用GROUP BY.非常感谢任何帮助,谢谢.

SELECT t0_.id AS id0,
       t0_.slug AS slug1,
       t0_.name AS name2,
       t0_.description AS description3,
       t0_.user_id AS user_id4
FROM tag t0_ 
    INNER JOIN customers_tags c2_ ON t0_.id = c2_.tag_id
        INNER JOIN customer c1_ ON c1_.id = c2_.customer_id
WHERE t0_.user_id = 1 AND COUNT(c1_.id) > 0
ORDER BY t0_.name ASC

Answer 1

您count()在where子句中使用了一个不允许的聚合函数.

聚合函数的条件需要进入HAVING子句

....
WHERE t0_.user_id = 1
HAVING count(c1_.id) > 0

当然,您需要使用GROUP BY来获得正确的结果(尽管MySQL可能会让您在不使用GROUP BY的情况下逃脱 - 但结果是不可预测的)