MySQL 创建存储过程注意项

DELIMITER //
CREATE PROCEDURE mes.ADD_USER_REAL_NAME()
BEGIN
  IF NOT EXISTS (SELECT * FROM information_schema.COLUMNS  WHERE 
            table_schema = 'test'  
            AND table_name = 'sys_user'  
            AND column_name = 'REAL_NAME') 
  THEN
     ALTER TABLE `sys_user` ADD COLUMN `REAL_NAME` VARCHAR(20) NULL COMMENT '真实姓名' AFTER `LoginName`;
  END IF;
END;
//