Managing & Using MySQL, 2nd Edition

Name

CREATE FUNCTION

Syntax

CREATE [AGGREGATE] FUNCTION name 
RETURNS return_type SONAME library

Description

The CREATE FUNCTION statement allows MySQL statements to access precompiled executable functions known as user-defined functions (UDFs). These functions can perform practically any operation, since they are designed and implemented by the user. The return value of the function can be STRING, for character data; REAL, for floating point numbers; or INTEGER, for integer numbers. MySQL will translate the return value of the C function to the indicated type. The library file that contains the function must be a standard shared library that MySQL can dynamically link into the server. See Chapter 14 for more information.

Example

CREATE FUNCTION multiply RETURNS REAL SONAME mymath