Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
722 views
in Technique[技术] by (71.8m points)

symfony - DQL query with joining table and two join

I have 2 entity:

/**
 * @ORMEntity
 * @ORMTable(name="users")
 */
class User
{
    /**
     * @ORMManyToMany(targetEntity="MyappUserBundleEntityGroup")
     * @ORMJoinTable(name="user_groups",
     *      joinColumns={@ORMJoinColumn(name="user_id", referencedColumnName="id")},
     *      inverseJoinColumns={@ORMJoinColumn(name="group_id", referencedColumnName="id")}
     * )
     */
    protected $groups;

    ...
}

and

/**
 * @ORMEntity(repositoryClass="MyappUserBundleRepositoryGroupRepository")
 * @ORMTable(name="groups")
 */
class Group
  ...

I cant find a way to create a DQL query which results SQL like this:

SELECT g.name, g.id, count( u.id )
FROM users u
LEFT JOIN user_groups ug ON u.id = ug.user_id
RIGHT JOIN groups g ON g.id = ug.group_id
GROUP BY g.id

I tried and failed whith:

$this->getEntityManager()
    ->createQuery('
        SELECT g.id, g.name, count(u.id) as usercount FROM MyappUserBundle:User u
        JOIN u.groups g
        GROUP BY g.id'
    );

since the result not contains the groups that has no user.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

It's a ManyToMany relation, don't event try to join on the relation table, only the related entity... Then, you were right with the RIGHT JOIN ... for a SQL query, but Doctrine automatically defines the jointure type from the FROM clause.

In DQL, only defined relations are managed by jointures, so you don't need USE or ON clauses...

What about this one ?

SELECT g.name, g.id, count( u.id )
FROM groups g
JOIN users u
GROUP BY g.id

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...