DELIMITER $$
DROP PROCEDURE IF EXISTS test_procedure $$
CREATE PROCEDURE test_procedure()
BEGIN
IF EXISTS(SELECT 1 FROM information_schema.COLUMNS
WHERE UPPER(table_schema) = UPPER('kirin')
AND UPPER(table_name) = UPPER('stu_info')
AND UPPER(列名) = UPPER('stu_name')
) THEN ALTER TABLE kirin.stu_info MODIFY stu_name VARCHAR(50);
終了 IF;
終了 $$
区切り文字 ;
CALL kirin.test_procedure();
存在する場合はプロシージャを削除 kirin.test_procedure;