PrimaryKey (EclipseLink 2.6.5, API Reference)

EclipseLink 2.6.5, API Reference

All Classes

Summary:
Required |
Optional

Detail:
Element

```
@Target(value=TYPE)
@Retention(value=RUNTIME)
public @interface PrimaryKey
```
The PrimaryKey annotation allows advanced configuration of the Id. A validation policy can be given that allows specifying if zero is a valid id value. The set of primary key columns can also be specified precisely.

Author:

James Sutherland

Since:

EclipseLink 1.1

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element and Description
`CacheKeyType`	`cacheKeyType` (Optional) Configures what cache key type is used to store the object in the cache.
`Column[]`	`columns` (Optional) Used to specify the primary key columns directly.
`IdValidation`	`validation` (Optional) Configures what id validation is done.

- Element Detail
  - validation
```
public abstract IdValidation validation
```
    (Optional) Configures what id validation is done. By default 0 is not a valid id value, this can be used to allow 0 id values.
    
    Default:
    
    org.eclipse.persistence.annotations.IdValidation.ZERO
  - cacheKeyType
```
public abstract CacheKeyType cacheKeyType
```
    (Optional) Configures what cache key type is used to store the object in the cache. By default the type is determined by what type is optimal for the class.
    
    Default:
    
    org.eclipse.persistence.annotations.CacheKeyType.AUTO
  - columns
```
public abstract Column[] columns
```
    (Optional) Used to specify the primary key columns directly. This can be used instead of @Id if the primary key includes a non basic field, such as a foreign key, or a inheritance discriminator, embedded, or transformation mapped field.
    
    Default:
    
    {}

EclipseLink 2.6.5, API Reference

All Classes

Summary:
Required |
Optional

Detail:
Element