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5.7. Auxiliary database objects

Auxiliary database objects allow for the CREATE and DROP of arbitrary database objects. In conjunction with Hibernate's schema evolution tools, they have the ability to fully define a user schema within the Hibernate mapping files. Although designed specifically for creating and dropping things like triggers or stored procedures, any SQL command that can be run via a java.sql.Statement.execute() method is valid (for example, ALTERs, INSERTS, etc.). There are essentially two modes for defining auxiliary database objects:
The first mode is to explicitly list the CREATE and DROP commands in the mapping file:
<hibernate-mapping>
    ...
    <database-object>
        <create>CREATE TRIGGER my_trigger ...</create>
        <drop>DROP TRIGGER my_trigger</drop>
    </database-object>
</hibernate-mapping>
The second mode is to supply a custom class that constructs the CREATE and DROP commands. This custom class must implement the org.hibernate.mapping.AuxiliaryDatabaseObject interface.
<hibernate-mapping>
    ...
    <database-object>
        <definition class="MyTriggerDefinition"/>
    </database-object>
</hibernate-mapping>
Additionally, these database objects can be optionally scoped so that they only apply when certain dialects are used.
<hibernate-mapping>
    ...
    <database-object>
        <definition class="MyTriggerDefinition"/>
        <dialect-scope name="org.hibernate.dialect.Oracle9iDialect"/>
        <dialect-scope name="org.hibernate.dialect.Oracle10gDialect"/>
    </database-object>
</hibernate-mapping>