This section describes the MySQL User-defined function CREATEFUNCTION. The following is the sample code. For more information, see
Mysql> delimiter $ mysql> create function myFunction-> (in_string VARCHAR (255),-> in_find_str VARCHAR (20),-> in_repl_str VARCHAR (20 )) -> returns varchar (255)-> BEGIN-> DECLARE l_new_string VARCHAR (255);-> DECLARE l_find_pos INT;-> SET l_find_pos = INSTR (in_string, in_find_str);-> IF (l_find_pos> 0) THEN-> SET l_new_string = INSERT (in_string, l_find_pos, LENGTH (in_find_str), in_repl_str ); -> ELSE-> SET l_new_string = in_string;-> end if;-> RETURN (l_new_string);-> END $ Query OK, 0 rows affected (0.00 sec) mysql> delimiter; mysql> select myFunction ('ABC', 'A', 'z'); + ------------------------- + | myFunction ('ABC', 'A ', 'Z') | + ------------------------- + | ZBC | + --------------------------- + 1 row in set (0.00 sec) mysql> drop function myFunction; Query OK, 0 rows affected (0.00 sec)