There are many instances in which you might repeatedly use some functionality. It would be handy if you were allowed to create a function that could be used as, and when, needed.
MySQL allows you to create FUNCTIONS that can be used this way.
Syntax:
CREATE FUNCTION (argument list) RETURNS DETERMINISTIC RETURN ();
I have chosen the method name as SUMSUM, since SUM is already available as a default function.
Now, when you use this function as below:
SELECT SUMSUM (5,6);
It results in the following:
+--------------+| SUMSUM (5,6) |+--------------+| 11 |+--------------+
In case you think that the Function created by you will be of no use henceforth, you can safely delete it with the following command.
DROP FUNCTION SUMSUM;