mysql 存储过程的应用_MySQL
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2022-05-29 18:24:12
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MySQL存储过程的创建
(1). 格式
MySQL存储过程创建的格式:CREATE PROCEDURE 过程名 ([过程参数[,...]])
[特性 ...] 过程体
这里先举个例子:
- mysql> DELIMITER //
- mysql> CREATE PROCEDURE proc1(OUT s int)
- -> BEGIN
- -> SELECT COUNT(*) INTO s FROM user;
- -> END
- -> //
- mysql> DELIMITER ;
注:
(1)这里需要注意的是DELIMITER //和DELIMITER ;两句,DELIMITER是分割符的意思,因为MySQL默认以";"为分隔符,如果我们没有声明分割符,那么编译器会把存储过程当成SQL语句进行处理,则存储过程的编译过程会报错,所以要事先用DELIMITER关键字申明当前段分隔符,这样MySQL才会将";"当做存储过程中的代码,不会执行这些代码,用完了之后要把分隔符还原。
(2)存储过程根据需要可能会有输入、输出、输入输出参数,这里有一个输出参数s,类型是int型,如果有多个参数用","分割开。
(3)过程体的开始与结束使用BEGIN与END进行标识。
这样,我们的一个MySQL存储过程就完成了,是不是很容易呢?看不懂也没关系,接下来,我们详细的讲解。
下面的例子主要用到了
Ⅰ. if-then -else语句
Ⅰ. FOUND_ROWS() 语句
#记录每天的步行、睡眠、体重、消耗卡路里等信息#userRecordDetail 表中,如果存在当天数据,则修改,否则新增#userRecord 表中,如果存在,则累加,否则新增#类型:1步行2睡眠3卡路里消耗4体重#CALL userRecord_create(1001,45,100,1000,1000,500,500,2,1);DROP PROCEDURE IF EXISTS pro_userRecord_stepNum; DELIMITER //CREATE PROCEDURE pro_userRecord_stepNum(IN p_userId INT,IN p_stepNum INT)BEGIN DECLARE RCount INT; -- 查看用户是否有详细记录 SELECT id FROM userRecordDetail WHERE userId = p_userId AND DATE(createTime) = CURDATE() LIMIT 1; SELECT FOUND_ROWS() INTO RCount; IF (RCount=0) THEN --查看userRecord是否有用户总记录信息,不存在,则添加,否则修改 SELECT idFROM userRecord WHERE userId = p_userId LIMIT 1; SELECT FOUND_ROWS() INTO RCount; IF(RCount = 0 )THEN INSERTINTO `userRecord`(`userId`,`totalStep`,`updateTime`,`createTime`) VALUES (p_userId,p_stepNum,NOW(),NOW()); ELSE UPDATE userRecord SET totalStep = totalStep+p_stepNum WHERE userId = p_userId; END IF;-- 结束 -- 插入一条用户记录详细信息 INSERTINTO `userRecordDetail`(`weigh`,`calorie`,`stepNum`,`userId`, `sleepTimes`,`lightSleepTimes`,`heavySleepTimes`, `wakeupNum`,`updateTime`,`createTime`) VALUES (0,0,p_stepNum, p_userId,0,0,0,0,NOW(),NOW()); ELSE --查看是否有用户总记录信息,不存在,则添加,否则修改 SELECT idFROM userRecord WHERE userId = p_userId LIMIT 1; SELECT FOUND_ROWS() INTO RCount; IF(RCount = 0 )THEN INSERTINTO `userRecord`(`userId`,`totalStep`,`updateTime`,`createTime`) VALUES (p_userId,p_stepNum,NOW(),NOW()); ELSE UPDATE userRecord SET totalStep = totalStep + p_stepNum WHERE userId = p_userId; END IF; -- 修改userRecordDetail UPDATE userRecordDetail SET stepNum = stepNum + p_stepNum WHERE userId = p_userId; END IF;END;//DELIMITER ; SHOW WARNINGS; SHOW CREATE PROCEDURE pro_userRecord_stepNum;CALL pro_userRecord_stepNum(1009,111);
Ⅰ. 创建表的语句如下:
DROP TABLE IF EXISTS `userRecord`;CREATE TABLE `userRecord` (`id` int(11) NOT NULL AUTO_INCREMENT,`userId` int(11) NOT NULL COMMENT 'fk',`totalStep` int(11) DEFAULT '0' COMMENT '总步数',`updateTime` datetime DEFAULT NULL,`createTime` datetime NOT NULL,PRIMARY KEY (`id`)) ENGINE=MyISAM AUTO_INCREMENT=8 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci COMMENT='用户记录总表';/*Data for the table `userRecord` */LOCK TABLES `userRecord` WRITE;insertinto `userRecord`(`id`,`userId`,`totalStep`,`updateTime`,`createTime`) values (1,1001,88000,'2014-05-16 14:16:50','2014-05-13 14:16:52'),(2,1002,35000,'2014-05-16 14:26:22','2014-05-12 14:26:24'),(3,1003,95000,'2014-05-16 14:28:00','2014-05-12 14:28:06'),(4,1007,150000,'2014-05-16 14:30:31','2014-04-28 14:30:33'),(5,1009,288,'2014-05-19 16:24:26','2014-05-19 16:24:26'),(6,1010,33,'2014-05-19 17:01:50','2014-05-19 17:01:50'),(7,1011,33,'2014-05-19 17:03:31','2014-05-19 17:03:31');UNLOCK TABLES;/*Table structure for table `userRecordDetail` */DROP TABLE IF EXISTS `userRecordDetail`;CREATE TABLE `userRecordDetail` (`id` int(11) NOT NULL AUTO_INCREMENT,`weigh` double DEFAULT '0' COMMENT '今日体重 kg',`calorie` int(11) DEFAULT '0' COMMENT '今日消耗卡路里',`stepNum` int(11) DEFAULT '0' COMMENT '今日步数',`userId` int(11) NOT NULL COMMENT 'fk',`sleepTimes` int(11) DEFAULT '0' COMMENT '今日睡眠时间 单位:分钟',`lightSleepTimes` int(11) DEFAULT '0' COMMENT '今日轻度睡眠时间 单位:分钟',`heavySleepTimes` int(11) DEFAULT '0' COMMENT '今日重度睡眠时间 单位:分钟',`wakeupNum` int(11) DEFAULT '0' COMMENT '今日唤醒次数',`updateTime` datetime DEFAULT NULL,`createTime` datetime NOT NULL,PRIMARY KEY (`id`)) ENGINE=MyISAM AUTO_INCREMENT=26 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci COMMENT='用户记录详细信息表';/*Data for the table `userRecordDetail` */LOCK TABLES `userRecordDetail` WRITE;insertinto `userRecordDetail`(`id`,`weigh`,`calorie`,`stepNum`,`userId`,`sleepTimes`,`lightSleepTimes`,`heavySleepTimes`,`wakeupNum`,`updateTime`,`createTime`) values (1,0,0,10000,1001,0,0,0,0,NULL,'2014-05-16 14:17:53'),(2,0,0,10000,1001,0,0,0,0,NULL,'2014-05-15 14:22:58'),(3,0,0,15000,1001,0,0,0,0,NULL,'2014-05-14 14:23:56'),(4,0,0,13000,1001,0,0,0,0,NULL,'2014-05-13 14:24:10'),(5,0,0,20000,1001,0,0,0,0,NULL,'2014-05-12 14:24:32'),(6,0,0,8000,1001,0,0,0,0,NULL,'2014-05-11 14:24:51'),(7,0,0,12000,1001,0,0,0,0,NULL,'2014-05-09 14:25:02'),(8,0,0,10000,1002,0,0,0,0,NULL,'2014-05-16 14:26:50'),(9,0,0,5000,1002,0,0,0,0,NULL,'2014-05-15 14:26:58'),(10,0,0,20000,1002,0,0,0,0,NULL,'2014-05-14 14:27:14'),(11,0,0,20000,1003,0,0,0,0,NULL,'2014-05-16 14:28:46'),(12,0,0,30000,1003,0,0,0,0,NULL,'2014-05-15 14:28:54'),(13,0,0,25000,1003,0,0,0,0,NULL,'2014-05-13 14:29:01'),(14,0,0,15000,1003,0,0,0,0,NULL,'2014-05-12 14:29:07'),(15,0,0,5000,1003,0,0,0,0,NULL,'2014-05-08 14:29:39'),(16,0,0,20000,1007,0,0,0,0,NULL,'2014-05-16 14:30:45'),(17,0,0,30000,1007,0,0,0,0,NULL,'2014-05-15 14:30:54'),(18,0,0,25000,1007,0,0,0,0,NULL,'2014-05-14 14:31:02'),(19,0,0,15000,1007,0,0,0,0,NULL,'2014-05-13 14:31:10'),(20,0,0,35000,1007,0,0,0,0,NULL,'2014-05-12 14:31:18'),(21,0,0,25000,1007,0,0,0,0,NULL,'2014-05-11 14:31:26'),(22,0,0,20000,1007,0,0,0,0,NULL,'2014-04-30 14:32:02'),(23,45,111,288,1009,600,100,500,2,'2014-05-19 16:24:26','2014-05-19 16:24:26'),(24,0,66,33,1010,0,0,0,0,'2014-05-19 17:01:50','2014-05-19 17:01:50'),(25,45,33,33,1011,600,100,500,0,'2014-05-19 17:03:31','2014-05-19 17:03:31');UNLOCK TABLES;
下面的例子主要用到了
Ⅰ. if-then -else语句