net.java.ao.schema
Annotation Type AutoIncrement


@Retention(value=RUNTIME)
@Target(value=METHOD)
public @interface AutoIncrement

Tags a specific method as representing a field who's value should be auto-generated by the database in some sort of numeric sequence (usually ascending order). Not all databases support this function as a field modifier. For example, PostgreSQL requires the use of the SERIAL type. Thus, this annotation imposes priority over the defined type and should only be used on int or long fields (short is also acceptable if great care is taken).

For databases which really have no way of supporting this exact functionality (like Oracle), implementation may be omitted as long as the 90% case is still covered. For example, the Oracle implementation of this property relies on the fact that PRIMARY KEY fields are already auto-generated if no value is specified.

This annotation is only relevant to migrations. It has no effect upon "runtime" entity usage.

Author:
Daniel Spiewak



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