What does JPA EntityManager.getSingleResult() return for a COUNT query?

Question

What does EntityManager.getSingleResult() return for a COUNT query?

So.. what is the precise runtime type of foo?

Object foo = em.createQuer         


        

Answer 1

NB : there's a difference between JQPL and Native query

Query query = em.createQuery("SELECT COUNT(p) FROM PersonEntity p " );

query.getSingleResult().getClass().getCanonicalName() --> java.lang.Long

Query query = em.createNativeQuery("SELECT COUNT(*) FROM PERSON " );

query.getSingleResult().getClass().getCanonicalName() --> java.math.BigInteger