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Criteria Query From Elements

The interfaces in this group are in use for setting a criteria query FROM clause.

Criteria Query Variables

The FROM clause in JPA queries (as in SQL) defines the query variables. Query variables are represented in criteria queries by descendant interfaces of the From interface:

Range variables (bound by an entity class) are represented by the Root subinterface:

Join variables (bound by an attribute of a preceding variable in the FROM clause) are represented by the Join subinterface and its descendant interfaces:

See the FROM in Criteria Queries section for more details and examples.

Join Fetch Elements

Join Fetch is managed in criteria queries by the following interfaces:

See the FROM in Criteria Queries section for more details and an example.

This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.