Customizing SQL Mappings for insertion and deletion are similar; all of these must declare how optimistic lock checking is performed. You can copy a template from the Hibernate startup log to get the correct order and number of parameters. Finally, you can also map stored functions in Hibernate. They have slightly different semantics and use cases. Mapping stored functions A stored function only has input parameters no output parameters. However, it can return a value. For example, a stored function can return the rank of a user: create or replace function GET_USER_RANK (IN_USER_ID int) return int is RANK int; begin select RANKING into RANK from USERS where USER_ID = IN_USER_ID; return RANK; end; drop function GET_USER_RANK This function returns a scalar number. The primary use case for stored functions that return scalars is embedding a call in regular SQL or HQL queries. For example, you can retrieve all users who have a higher rank than a given user: String q = “from User u where u.ranking > get_user_rank(:userId)”; List result = session.createQuery(q) .setParameter(”userId”, 123) .list(); This query is in HQL; thanks to the pass-through functionality for function calls in the WHERE clause (not in any other clause though), you can call any stored function in your database directly. The return type of the function should match the
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