Notice: this Wiki will be going read only early in 2024 and edits will no longer be possible. Please see: https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/wikis/Wiki-shutdown-plan for the plan.
Difference between revisions of "EclipseLink/UserGuide/JPA/Basic JPA Development/Entities/Ids/Generating and Configuring Entity Identities"
< EclipseLink | UserGuide | JPA | Basic JPA Development
m |
|||
| Line 3: | Line 3: | ||
|toc=n | |toc=n | ||
|eclipselink=y | |eclipselink=y | ||
| − | |eclipselinktype=JPA}} | + | |eclipselinktype=JPA}} |
| − | + | ||
| − | + | ||
| − | + | = Generating and Configuring Entity Identity = | |
| − | + | Every entity must have a persistent identity, which is an equivalent of a primary key in a database table that stores the entity state. | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | You can | + | By default, the [[EclipseLink/UserGuide/JPA/Basic JPA Development/Configuration/JPA/persistence.xml|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: | ||
| + | |||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/Id|@Id]] | ||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/IdClass|@IdClass]] | ||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/EmbeddedId|@EmbeddedId]] | ||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/GeneratedValue|@GeneratedValue]] | ||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/TableGenerator|@TableGenerator]] | ||
| + | *[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Entity/SequenceGenerator|@SequenceGenerator ]] | ||
| + | You can also use these annotations to fine-tune how your database maintains the identity of your entities. | ||
| + | <br> | ||
{{EclipseLink_JPA | {{EclipseLink_JPA | ||
Revision as of 11:45, 29 March 2011
EclipseLink JPA
| EclipseLink | |
| Website | |
| Download | |
| Community | |
| Mailing List • Forums • IRC • mattermost | |
| Issues | |
| Open • Help Wanted • Bug Day | |
| Contribute | |
| Browse Source |
Generating and Configuring Entity Identity
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 |
|
 EclipseLink Home
JPA User Guide: |
||
| How to contribute to this guide... | ||
