JPA: caching queries

Question

I\'m using JPA to load and persist entities in my Java EE-based web application. Hibernate is used as an implementation of JPA, but I don\'t use Hibernate-specific features and

Answer 1

What you want is a NamedQuery. On your Order entity you put:

@NamedQueries({
    @NamedQuery( name = "getOrderByCustomerId", query = "SELECT o FROM Order o WHERE o.customerId = :customerId")
})

Then in your DAO use em.createNamedQuery("getOrderByCustomerId") instead of recreating the query.