带有OR的JPQL不返回预期结果

Question

I want to get all clients which have no users at all or a specific user in the list. But I always get wrong results. If I seperate the one into two queries it works like a charm. Only connecting them fails.

I hope you can help me ;)

Here's my Query:

Query q = em.createQuery("SELECT c FROM Clients c WHERE SIZE(c.usersList) = 0 OR ?1 MEMBER OF c.usersList"); q.setParameter(1, user);

Answer 1

Using LEFT JOIN instead of implicit join coming from MEMBER OF helps:

SELECT c 
FROM Client c LEFT JOIN c.usersList u 
WHERE SIZE(c.usersList) = 0 OR u = ?1