Types of functions

There are several ways to classify functions. One way to classify functions is as built-in, user-defined, or generated user-defined functions for distinct types.

Another way to classify functions is as aggregate, scalar, or table functions, depending on the input data values and result values.


33.
Built-in functions are implemented internally by the database manager, so an associated program or service program object does not exist for a built-in function. Furthermore, the catalog does not contain information about built-in functions. However, built-in functions can be treated as if they exist in QSYS2 and a built-in function name can be qualified with QSYS2.