ObjectDB ObjectDB

JPA does not seem to be db agnostic

#1

The following jpa code works with mysql but not with objectdb. Why would this happen? The provider the both jpas is the same: EclipseLink. The link for the one used with mysql is org.eclipse.persistence.jpa.PersistenceProvider; the one for objectdb is com.objectdb.jpa.Provider (per the tutorials).

    public Friendship getFriendship(String username) {
        CriteriaBuilder criteriaBuilder = em.getCriteriaBuilder();
        CriteriaQuery<Friendship> query = criteriaBuilder.createQuery(Friendship.class);
        Root<Friendship> root = query.from(Friendship.class);
        Path<String> path = root.<String>get("username");
        query.where(criteriaBuilder.equal(path, username));
        return em.createQuery(query).getSingleResult();
    }
edit
delete
#2

A valid JPQL query must include SELECT, otherwise the query is incomplete.

Some JPA implementations extend the standard JPQL by supporting queries with no SELECT.

ObjectDB Support
edit
delete

Reply

To post on this website please sign in.