Doctrine JOIN 与 DQL 中的子查询

Question

我有这个 SQL：

SELECT
s.id,
e.exception,
s.name,
w.url,
w.web_id,
w.active,
w.suspended,
r.email,
p.name as partner,
p.id as partnerId,
group_concat(c.name) names,
group_concat(c.email) emails,
group_concat(c.tel) tels
FROM
service s
JOIN web w ON s.web_id = w.id
JOIN rus r ON w.rus_id = r.id
JOIN partner p ON r.partner_id = p.id
LEFT JOIN exception e ON e.service_id = s.id
JOIN contact c ON c.partner_id = c.id
where c.main = 1 or c.important = 1
group by s.id

当我尝试将其转换为 DQL 时

$result = $this->_em
    ->createQuery(
        'SELECT s.name, w.webId, r.email, p.name as PartnerName
         FROM App\Model\Database\Entity\Service s
         JOIN App\Model\Database\Entity\Web w WITH s.web = w.id
         JOIN App\Model\Database\Entity\Rus r WITH w.rus = r.id
         JOIN App\Model\Database\Entity\Partner p WITH r.partner = p.id
         LEFT JOIN App\Model\Database\Entity\Exception e WITH e.service = s.id
         LEFT JOIN (SELECT
         p.id,
         group_concat(c.name) names,
         group_concat(c.tel) tels,
         group_concat(c.email) emails
         FROM
         App\Model\Database\Entity\Partner p
         LEFT JOIN App\Model\Database\Entity\Contact c WITH c.partner = p.id
         where c.main = 1 or c.important = 1
         group by p.id) test
         WHERE test.id = p.id'
    )->getResult();

return new ArrayCollection($result);

我明白了：

[Semantical Error] line 0, col 452 near 'JOIN (SELECT\r\n ': Error: Subquery is not supported here

使用 QueryBuilder 是一样的..

在 DQL 或使用 QueryBuilder 中使用左连接和子查询有什么技巧吗？

谢谢

Answer 1

正如#3542中的回答

DQL 是关于查询对象的。支持 FROM 中的子选择 子句表示 DQL 解析器无法构建结果集 不再映射（因为子查询返回的字段可能不匹配 对象了）。

最好的办法是使用 sql

$conn = $this->getEntityManager()->getConnection();
$sql = 'Your query';
$stmt = $conn->prepare($sql);
$stmt->execute(); //Bind what parameters you need

Answer 2

当您可以使用连接和聚合处理它时，我认为您不需要子查询。就像在主查询中一样，加入您的 contact 实体并为您想要的结果集执行聚合。我已经更新了 group by 子句并添加了 select 子句中的所有非聚合列，因此即使启用了 mysql 的严格模式，此查询也将有效，请参阅MySQL Handling of GROUP BY，它还将根据分组条件消除重复行

在 SQL 中是这样的

SELECT
    s.id,
    s.name,
    e.exception,
    w.url,
    w.web_id,
    w.active,
    w.suspended,
    r.email,
    p.name as partnerName,
    p.id as partnerId,
    group_concat(c.name) names,
    group_concat(c.email) emails,
    group_concat(c.tel) tels
FROM service s
    left join exception e ON e.service_id = s.id
    join web w ON s.web_id = w.id
    join rus r ON w.rus_id = r.id
    join partner p ON r.partner_id = p.id
    join contact c ON c.partner_id = c.id 
WHERE c.main = 1 or c.important = 1
GROUP BY s.id,
        s.name,
        e.exception,
        w.url,
        w.web_id,
        w.active,
        w.suspended,
        r.email,
        p.name,
        p.id

我相信你需要添加一个扩展来支持 Mysql 的 GROUP_CONCAT 函数在默认情况下，这不包括在教义 orm 中。

要添加对GROUP_CONCAT in doctrine 的支持，您可以按照链接答案中提到的步骤进行操作。注册后，您可以将原始 SQL 转换为 DQL

SELECT  s.id,
        s.name,
        e.exception,
        w.url,
        w.web_id,
        w.active,
        w.suspended,
        r.email,
        p.id as partnerId,
        p.name as partnerName,
        GROUP_CONCAT(c.name) contactNames,
        GROUP_CONCAT(c.email) contactEmails,
        GROUP_CONCAT(c.tel) contactTels
FROM App\Model\Database\Entity\Service s
    LEFT JOIN App\Model\Database\Entity\Exception e WITH e.service = s.id
    JOIN App\Model\Database\Entity\Web w WITH s.web = w.id
    JOIN App\Model\Database\Entity\Rus r WITH w.rus = r.id
    JOIN App\Model\Database\Entity\Partner p WITH r.partner = p.id
    JOIN App\Model\Database\Entity\Contact c WITH c.partner = p.id
WHERE c.main = 1 or c.important = 1
GROUP BY s.id,
        s.name,
        e.exception,
        w.url,
        w.web_id,
        w.active,
        w.suspended,
        r.email,
        p.name,
        p.id
    

或者另一种方法是使用ResultSetMapping 学说类，您可以在其中执行原始 SQL 并将结果映射到相应的实体上

$rsm = new ResultSetMapping;
$rsm->addEntityResult('App\Model\Database\Entity\Service', 's');
$rsm->addFieldResult('s', 'id', 'id');
$rsm->addFieldResult('s', 'name', 'name');
$rsm->addJoinedEntityResult('App\Model\Database\Entity\Exception' , 'e', 's', 'exception');
$rsm->addFieldResult('e', 'exception', 'exception');
//.... other relations
$rsm->addJoinedEntityResult('App\Model\Database\Entity\Partner' , 'p', 'r', 'partner');
$rsm->addFieldResult('p', 'partnerName', 'name');
$rsm->addScalarResult('contactNames', 'contactNames');
// ... and so on

$sql = 'SELECT s.id, e.exception ... FROM service s JOIN ... WHERE ... GROUP BY s.id, e.exception ...';
$query = $this->_em->createNativeQuery($sql, $rsm);
$data = $query->getResult();