User-Defined Functions Overview

An introduction to User-Defined Functions (UDFs) in MariaDB, explaining how they extend the server's functionality by adding new native-like functions.

A user-defined function (UDF) is a historical way to extend MariaDB with a new function that works similar to a native (built-in) MariaDB function such as ABS( ) or CONCAT( ). It was introduced in 1998 and is generally limited to supporting features that existed at that time.

Statements making use of user-defined functions are not safe for replication.

For an example, see sql/udf_example.cc in the source tree. For a collection of existing UDFs go to the UDF Repository on GitHub.

There are alternative ways to add a new function: a native function, which requires modifying and compiling the server source code; a function plugin; or a stored function.