A powerful query framework offers the ability to query across entities and their relationships without having to use concrete foreign keys or database columns. Queries may be expressed in JP QL, a query language that is modeled after SQL for its familiarity but is not tied to the database schema, or defined using the criteria API. Queries use a schema abstraction that is based on the entity model as opposed to the columns in which the entity is stored. Java entities and their attributes are used as the query schema, so knowledge of the database-mapping information is not required. The queries will eventually get translated by the JPA implementa...
Test of Quotes. It's is valid.
Share this highlighthttp://www.safaribooksonline.com/a/pro-jpa-2/223272/