JPA JPQL: select items when attribute of item (list/set) contains another item

问题

public class Document extends Model {
... 
@ManyToMany
public Set<User> accessors;
...
}

I want to select all Documents which accessors contain a certain user. I have just minimal experiences with SQL and no experiences with JPQL. So how to do that?

thanks in advance

回答1:

SELECT d FROM Document AS d WHERE :user MEMBER OF d.accessors

Should be what you need, and it is simpler than joining tables. Just dont forget to use the user as a parameter instead of using its id:

query.setParameter("user", user);

回答2:

select distinct d from Document d inner join d.accessors a where a.id = :id

You should learn how SQL joins work, and then learn how to use joins in JPQL. That's essential. You'll find plenty of tutorials online. Google is your friend.

来源：https://stackoverflow.com/questions/8339889/jpa-jpql-select-items-when-attribute-of-item-list-set-contains-another-item