-- 函数：某用户是否存在
DROP FUNCTION IF EXISTS is_user_exist;
DELIMITER //
CREATE FUNCTION is_user_exist(name varchar(15), pwd varchar(10)) RETURNS tinyint
BEGIN
    DECLARE r tinyint;
    select count(*) into r from user where name=name and pwd=md5(pwd);
    return r;
END;//
DELIMITER ;

-- 过程：执行更新时间
DROP PROCEDURE IF EXISTS update_last_reply_time;
DELIMITER //
CREATE PROCEDURE update_last_reply_id(reply_id int, topic_id int)
BEGIN
    update topic set last_reply_id=reply_id where id=topic_id;
END;//                           
DELIMITER ;
-- 单行语法：create procedure procedure_name() select * from table_name;