Simplify your SQL SELECT statements, provide an interface to pass parameters to create dynamic tables, automatically log access to tables, and create a single point of maintenance for the SQL code you use repeatedly.
Written by Jim Staton
In my previous article, "Reuse Your RPG Code with SQL User-Defined Functions," I discussed how you could reuse RPG business logic in SQL by taking an RPG program or service program that returns a single value and then using the SQL CREATE FUNCTION command to make the business logic available to any high-level language (HLL), such as PHP or Java, or any tool that uses SQL to access data on your system. There are times, however, when you might want a function that returns not just a single value but a set of values or even a table. In that case, you could consider using a User-Defined Table Function (UDTF).