79 words
MapKey.name - JPA annotation element
Annotation Elementjavax.persistence.MapKey
String name
(Optional) The name of the persistent field or property of the
associated entity that is used as the map key.
Default: If the
name element is not specified, the primary key of the
associated entity is used as the map key. If the
primary key is a composite primary key and is mapped
as IdClass, an instance of the primary key
class is used as the key.
- Default value:
- ""
- Since:
- JPA 1.0
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.
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.
Which JPA is Faster?
See a comparison of Hibernate, EclipseLink, OpenJPA, DataNucleus, MySQL, PostgreSQL, Derby, HSQLDB, DB4O by Versant, H2 Database, SQLite and ObjectDB
in the JPA Benchmark.
