搜索与Doctrine2的多对多关系

Question

This is probably an easy one but I can't figure it out nor find an answer.

I have a simple Article and ArticleTag Entities with many to many relationship. How can I get all articles with a certain tag (or tags)?

My following tries:

$qb = $repository->createQueryBuilder('a')
    // ...
    ->andWhere('a.tags = :tag')
    ->setParameter('tag', 'mytag')
    // ...

or

    ->andWhere(':tag in a.tags')
    ->setParameter('tag', 'mytag')

...didn't work. Thanks!

Answer 1

And the winner is ... drumroll, please ...

$qb = $repository->createQueryBuilder('a')
    // ...
    ->andWhere(':tag MEMBER OF a.tags');
    ->setParameter('tag', $tag);
    // ...

Thanks to everyone who has taken the time to read and think about my question!

Answer 2

我想你可以提供这个例子（来自文档）：

$query = $em->createQuery('SELECT u.id FROM CmsUser u WHERE EXISTS (SELECT p.phonenumber FROM CmsPhonenumber p WHERE p.user = u.id)');