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Difference between revisions of "EclipseLink/UserGuide/JPA/Basic JPA Development/Entities/Ids/Generating and Configuring Entity Identities"
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You can generate and/or configure the identity of your entities by using the following annotations: | You can generate and/or configure the identity of your entities by using the following annotations: | ||
*[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/Id|@Id]] | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/Id|@Id]] | ||
| − | *@IdClass | + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/IdClass|@IdClass]] |
* @EmbeddedId | * @EmbeddedId | ||
* @GeneratedValue | * @GeneratedValue | ||
Revision as of 08:43, 17 June 2010
Entity
Every entity must have a persistent identity, which is an equivalent of a primary key in a database table that stores the entity state.
By default, the EclipseLink persistence provider assumes that each entity has at least one field or property that serves as a primary key.
You can generate and/or configure the identity of your entities by using the following annotations:
You can also use these annotations to fine-tune how your database maintains the identity of your entities.
 Mapping |
@Id |
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JPA User Guide: |
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