IN clause with a composite primary key in JPA criteria

Question

I have a table named group_table in MySQL with only two columns user_group_id and group_id (both of them are of type VARCHAR). Both of these columns together form a composite primary key.

I need to execute a statement using a sub-select IN() to select rows based on a list of values passed to the query.

@Override
@SuppressWarnings("unchecked")
public List<GroupTable> getList(List<GroupTable> list)
{
    CriteriaBuilder criteriaBuilder=entityManager.getCriteriaBuilder();
    CriteriaQuery<GroupTable> criteriaQuery=criteriaBuilder.createQuery(GroupTable.class);
    Root<GroupTable> root = criteriaQuery.from(entityManager.getMetamodel().entity(GroupTable.class));
    criteriaQuery.where(root.in(list));
    return entityManager.createQuery(criteriaQuery).getResultList();
}

The implementation produces the following query.

SELECT group_id, 
       user_group_id 
FROM   projectdb.group_table 
WHERE  ((?, ?) IN ((?, ?), (?, ?))) 

/*Binding parameters.*/
bind => [null, null, ROLE_AAA, aaa, ROLE_BBB, aaa]

Please notice that the first two parameters which are about the composite key itself are null. They should be user_group_id and group_id respectively.

Why are they not substituted in the parameter list?

---

While I'm not interested in forming a composite primary key in a table, this is (likely) mandatory for JAAS I'm using for authentication.

_{In this scenario, the query returns the same list as it is supplied from the database which is needless in reality. I actually need this query for deletion of multiple rows.}

Answer 1

Try this

        CriteriaBuilder cb = entityManager.getCriteriaBuilder();
        CriteriaQuery<GroupTable> cq = cb.createQuery(GroupTable.class);
        Root<GroupTable> r = cq.from(GroupTable.class);
        Expression<EntityPK> exp = r.get("id"); //EntityPK is your primary composite key class and id is the property name of primary key in GroupTable entity
        Predicate predicate = exp.in(list);
        cq.select(r).where(predicate);

        entityManager.createQuery(cq).getResultList();

I have a following table with below structure

create table EntityA (
        col1 integer not null,
        col2 integer not null,
        description varchar(255),
        primary key (col1, col2)
    )

Following are the entity and composite key classes

@Entity
public class EntityA implements Serializable {

    @EmbeddedId
    private EntityPK id;
    private String description;

// getters, setteres    
    ...........................
    ............................


    }


@Embeddable
public class EntityPK implements Serializable {

    private int col1;
    private int col2;

// getters, setters, hashcode, equals etc

My test code is

 CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery<EntityA> cq = cb.createQuery(EntityA.class);
        Root<EntityA> r = cq.from(EntityA.class);
        Expression<EntityPK> exp = r.get("id");
        Predicate predicate = exp.in(list);
        cq.select(r).where(predicate);
        em.createQuery(cq).getResultList();

The resulting SQL is

select
        entitya0_.col1 as col1_0_,
        entitya0_.col2 as col2_0_,
        entitya0_.description as descript3_0_ 
    from
        EntityA entitya0_ 
    where
        entitya0_.col1=? 
        and entitya0_.col2=? 
        or entitya0_.col1=? 
        and entitya0_.col2=? 
        or entitya0_.col1=? 
        and entitya0_.col2=?