I didn’t understand the differenze between JPAContainer and SQLContainer, someone could explain me please ??
Two different techonoliges. SQLContainer uses, well, SQL to query a database directly. JPA stands for
Java Persistance API
and uses entities more directly. JPA is an abstraction of the database. For example the frameworks EclipseLink and Hibernate provide JPA support.
Compare SQL
SELECT * FROM Employee WHERE pay>3000;
with JPA
CriteriaQuery cq = cb.createQuery();
Root e = cq.from(Employee.class);
cq.where(cb.greaterThan(e.get("pay"), 3000));
Query query = em.createQuery(cq);
List<Employee> result = query.getResultList();
JPA has also JPQL which is quite close to SQL, and it can also be queried directly with SQL.