Unnecessary INNER JOIN with Criteria

[Darlan Moraes]

Hello,

I'm working on a method in which a given table needs to join with another and with a field of the second table still another comparison do with it. Something like:

SELECT * FROM tab1 INNER JOIN tab2 WHERE tab2.id = (SELECT MAX(id) FROM tab2)

The method is as follows:

CriteriaBuilder cb = manager.getCriteriaBuilder();  
CriteriaQuery<Subs> c = cb.createQuery(Subs.class);  
Root<Subs> subs = c.from(Subs.class);  
Subquery<Number> sq = c.subquery(Number.class);  
Root<Auth> auth = sq.from(Auth.class);  
sq.select(cb.max(auth.get("authId").as(Number.class)));           
sq.where(cb.equal(auth.get("target"), target));  
List<Predicate> predicates = new ArrayList<Predicate>();  
if (target != null)  
    predicates.add(cb.equal(subs.get("target"), target));  
                          
predicates.add(subs.get("Auths").get("authId").in(sq));  
  
c.where(predicates.toArray(new Predicate[predicates.size()]));

And the only mapping that exists is unidirectional, from Subs to Auth:

@OneToMany(fetch=FetchType.EAGER)  
@JoinColumn(name="SubsIdAuth")  
private List<Auth> Auths;

This works, but OpenJPA does the following:

FROM tab_subs t0 INNER JOIN tab_auth t1 ON t0.CodSubs = t1.SubsId INNER JOIN tab_auth t5 ON t0.CodSubs = t5.SubsId

Does anyone know how to avoid this second join?