程式師世界 >> 數據庫知識 >> MYSQL數據庫 >> 關於MYSQL數據庫 >> MySql學習心得之存儲過程

MySql學習心得之存儲過程

編輯：關於MYSQL數據庫

先來看段mysql查詢文章回復語句：

復制代碼代碼如下:
#查詢文章回復
-- ----------------------------
-- Procedure structure for `sp_select_reply_article`
-- ----------------------------
DROP PROCEDURE IF EXISTS `sp_select_reply_article`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_select_reply_article`(IN `ra_id` int,IN `pagefrom` int,IN `pagesize` int)
BEGIN
         #Routine body goes here...
         SET @ra_id = ra_id;
         SET @pagefrom = pagefrom;
         SET @pagesize = pagesize;
         SET @ssra = CONCAT('SELECT * FROM gk_article WHERE id = ? LIMIT ?,?');
         PREPARE sqlquery FROM @ssra;
         EXECUTE sqlquery USING @ra_id,@pagefrom,@pagesize;
END

DELIMITER ;

#技術點1：MySql5.1不支持LIMIT參數（MySql5.5就支持了），如果編寫存儲過程時使用LIMIT做變量，那是需要用動態SQL來構建的，而這樣做性能肯定沒有靜態SQL好。主要代碼如下：

復制代碼代碼如下:
         SET @ssra = CONCAT('SELECT * FROM gk_article WHERE id = ? LIMIT ?,?');
         PREPARE sqlquery FROM @ssra;
         EXECUTE sqlquery USING @ra_id,@pagefrom,@pagesize;

#技術點2：如果同時需要返回受影響行數需要在語句後面添加語句：ROW_COUNT()函數，兩條語句之間需要“;”分隔。

復制代碼代碼如下:
#更新數據
-- ----------------------------
-- Procedure structure for `sp_update_permission`
-- ----------------------------
DROP PROCEDURE IF EXISTS `sp_update_permission`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_update_permission`(IN `puser_uid` varchar(20),IN `plevel` int,IN `ppower` int)
BEGIN
         #Routine body goes here...

         SET @puser_uid = puser_uid;
         SET @plevel = plevel;
         SET @ppower = ppower;
         UPDATE gk_permission SET `level` = @plevel, power = @ppower WHERE user_uid = CONVERT(@puser_uid USING utf8) COLLATE utf8_unicode_ci;
END

DELIMITER ;

#技術點3：MySQL進行字符串比較時發生錯誤（Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '='），解決方法：將比較等式一邊進行字符串轉換，如改為“CONVERT(b.fullCode USING utf8) COLLATE utf8_unicode_ci”，主要代碼如下：

復制代碼代碼如下:
UPDATE gk_permission SET `level` = @plevel, power = @ppower WHERE user_uid = CONVERT(@puser_uid USING utf8) COLLATE utf8_unicode_ci;

復制代碼代碼如下:
#插入數據
-- ----------------------------
-- Procedure structure for `sp_insert_user`
-- ----------------------------
DROP PROCEDURE IF EXISTS `sp_insert_user`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_insert_user`(IN `uid` varchar(20),IN `upw` varchar(32),IN `name` varchar(20),IN `sex` int,IN `phone` varchar(20),IN `u_id` int,IN `s_id` int,IN `j_id` int)
BEGIN
         #Routine body goes here...
         SET @uid = uid;
         SET @upw = upw;
         SET @uname = uname;
         SET @sex = sex;
         SET @phone = phone;
         #由於外鍵約束，所以添加的外鍵字段需要在對應外鍵所在表有相應數據
         SET @u_id = u_id;
         SET @s_id = s_id;
         SET @j_id = j_id;
         SET @verifytime = DATE('0000-00-00');
         INSERT INTO gk_user(uid,upw,uname,sex,phone,u_id,s_id,j_id,verifytime)
　　　　　　　VALUES(@uid,@upw,@uname,@sex,@phone,@u_id,@s_id,@j_id,@verifytime);
         #查詢結果會自動返回受影響行數
END

DELIMITER ;

復制代碼代碼如下:
#根據ID刪除數據
-- ----------------------------
-- Procedure structure for `sp_delete_exchange_by_id`
-- ----------------------------
DROP PROCEDURE IF EXISTS `sp_delete_exchange_by_id`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_delete_exchange_by_id`(IN `eid` int)
BEGIN
         #Routine body goes here...
         SET @eid = eid;
         DELETE FROM gk_exchange WHERE id = @eid;
END

DELIMITER ;

復制代碼代碼如下:
#通過賬號查詢用戶或者管理員
-- ----------------------------
-- Procedure structure for `sp_select_user_by_uid`
-- ----------------------------
DROP PROCEDURE IF EXISTS `sp_select_user_by_uid`;
DELIMITER ;;
CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_select_user_by_uid`(IN `uid` varchar(20),IN `getAdmin` int)
BEGIN
         #Routine body goes here...
         SET @uid = uid;
         #SET @getadmin = getAdmin;
         #查詢管理員
         IF (getAdmin = 1) THEN
                   SELECT us.*, un.`name`, se.`name`, jo.`name`, pe.`level`, pe.power FROM gk_user AS us, gk_unit AS un, gk_section AS se, gk_jobtitle AS jo, gk_permission AS pe WHERE us.u_id = un.id AND us.s_id = se.id AND us.j_id = jo.id AND us.uid = pe.user_uid AND us.uid = CONVERT(@uid USING utf8) COLLATE utf8_unicode_ci;
         END IF;
         #查詢用戶
         IF (getAdmin = 0) THEN
                   SELECT us.*, un.`name`, se.`name`, jo.`name` FROM gk_user AS us, gk_unit AS un, gk_section AS se, gk_jobtitle AS jo WHERE us.u_id = un.id AND us.s_id = se.id AND us.j_id = jo.id AND us.uid = CONVERT(@uid USING utf8) COLLATE utf8_unicode_ci;
         END IF;
END

DELIMITER ;