I would like to return a List of Integers from a
javax.persistence.EntityManager.createNativeQuery call
Why is the following incorrect?
entityManager.createNativeQuery("Select P.AppID From P", Integer.class);
specifically why do I get "...Unknown entity: java.lang.Integer"
Would I have to create an entity class that has a single field that is an Integer ?
Thanks
That doesn't work because the second parameter should be a mapped entity and of course Integer is not a persistent class (since it doesn't have the @Entity annotation on it).
for you you should do the following:
Query q = em.createNativeQuery("select id from users where username = :username");
q.setParameter("username", "lt");
List<BigDecimal> values = q.getResultList();
or if you want to use HQL you can do something like this:
Query q = em.createQuery("select new Integer(id) from users where username = :username");
q.setParameter("username", "lt");
List<Integer> values = q.getResultList();
Regards.