ASA SQL User's Guide
Using Procedures, Triggers, and Batches
User-defined functions are a class of procedures that return a single value to the calling environment. Adaptive Server Anywhere treats all user-defined functions as idempotent unless they are declared NOT DETERMINISTIC.
Idempotent functions return a consistent result for the same parameters and are free of side effects. Two successive calls to an idempotent function with the same parameters return the same result, and have no unwanted side-effects on the query's semantics.
For more information about non-deterministic and deterministic functions, see Function caching.
This section introduces creating, using, and dropping user-defined functions.
Creating user-defined functions
Calling user-defined functions
Dropping user-defined functions
Permissions to execute user-defined functions