Allows CREATE and DROP of arbitrary database objects, in conjunction with Hibernate's schema evolution tools, to provide 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, really any SQL command that can be run via a java.sql.Statement.execute() method is valid here (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 out 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 which knows how to construct 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 such that they only apply when certain dialects are used.

<hibernate-mapping>
    ...
    <database-object>
        <definition class="MyTriggerDefinition"/>
        <dialect-scope name="org.hibernate.dialect.Oracle9Dialect"/>
        <dialect-scope name="org.hibernate.dialect.OracleDialect"/>
    </database-object>
</hibernate-mapping>