CREATE DATABASE IF NOT EXISTS sample;

USE sample;

DROP TABLE IF EXISTS sample_data;

CREATE TABLE IF NOT EXISTS sample_data (

  id int(10) unsigned

) ENGINE=MyISAM;

DROP FUNCTION IF EXISTS udf_example;

DELIMITER $$

CREATE FUNCTION udf_example (cnt INT(10) UNSIGNED) RETURNS int(10) unsigned

BEGIN

  DECLARE i, j INT UNSIGNED DEFAULT 0;

  WHILE i < cnt

  DO 

    SELECT max(id) FROM sample_data

    INTO j;

    SET i = i + 1;

  END WHILE;

  RETURN cnt;

END

$$

DELIMITER ;

SHOW GLOBAL STATUS LIKE 'Memory_used';

SELECT udf_example(10000);

SHOW GLOBAL STATUS LIKE 'Memory_used';

SELECT udf_example(10000);

SHOW GLOBAL STATUS LIKE 'Memory_used';

SELECT udf_example(10000);

SHOW GLOBAL STATUS LIKE 'Memory_used';

DROP FUNCTION IF EXISTS udf_example;

SHOW GLOBAL STATUS LIKE 'Memory_used';