mysql中创建自定义存储过程，并使用游标案例

DELIMITER //  

DROP PROCEDURE IF EXISTS `test` //  

CREATE PROCEDURE `test` ()  

BEGIN  

 DECLARE  no_results,le_numbers,med_numbers,fee_numbers INT DEFAULT 0;  /*定义变量*/ 

 DECLARE  r_hid LONG;  

 DECLARE  cur_hid CURSOR FOR SELECT hid from hospital where `status` = 0;  /*First: Delcare a cursor,首先这里对游标进行定义*/  
 #条件处理必须在游标声明之后声明
 DECLARE  CONTINUE HANDLER FOR NOT FOUND  SET  no_results = 1; /*when "not found" occur,just continue,这个是个条件处理,针对NOT FOUND的条件*/  

/* for  loggging information 创建个临时表格来保持*/  

 /* CREATE TEMPORARY TABLE infologs (  

  plid INT (11) NOT NULL AUTO_INCREMENT COMMENT '主键',
	hid INT (11) COMMENT '医院id',
	level VARCHAR (20) COMMENT '会员类型名',
	created datetime COMMENT '创建时间',
	modified datetime COMMENT '修改时间',
	`status` TINYINT (2) COMMENT '状态 0.正常 1.删除',
	discount decimal(3,1) default 10.0 comment '折扣',
	PRIMARY KEY (`plid`)

 );  
 */

 OPEN  cur_hid; /*Second: Open the cursor 接着使用OPEN打开游标*/  

 FETCH  cur_hid INTO r_hid; /*Third: now you can Fetch the row 把第一行数据写入变量中,游标也随之指向了记录的第一行*/  

 REPEAT  

 SELECT  count(*) INTO le_numbers  

 FROM  patient_level  

 WHERE hid = r_hid;  

 IF  le_numbers = 0 THEN  

 /*INSERT INTO patient_level(hid,level,discount,status,created) */
INSERT INTO patient_level(hid,level,discount,status,created)
 VALUES (r_hid,'普通会员',10,0,NOW()),(r_hid,'银牌会员',10,0,NOW()),(r_hid,'金牌会员',10,0,NOW()),(r_hid,'钻石会员',10,0,NOW());

 END  IF;

SELECT  count(*) INTO med_numbers FROM  med_item  WHERE hid = r_hid; 

IF  med_numbers = 0 THEN  

INSERT INTO med_item(hid,name,duration,status,created) VALUES 
(r_hid,'医学验光',30,0,NOW()),(r_hid,'视功能检查',30,0,NOW()),(r_hid,'常规复查',30,0,NOW()),(r_hid,'OK镜验配',60,0,NOW()),(r_hid,'视觉训练',60,0,NOW());
 END  IF;


SELECT  count(*) INTO fee_numbers  FROM  fee_category  WHERE hid = r_hid; 
IF  fee_numbers = 0 THEN  

insert into fee_category(superior,hid,name,type,status,created) values (1,r_hid,'挂号费',1,0,now()),(1,r_hid,'检查费',1,0,now()),(1,r_hid,'手术费',1,0,now())
,(3,r_hid,'镜片类',1,0,now()),(3,r_hid,'镜架类',1,0,now()),(3,r_hid,'隐形眼镜类',1,0,now()),(3,r_hid,'太阳镜类',1,0,now()),(3,r_hid,'配件类',1,0,now()),
(2,r_hid,'中药类',1,0,now()),(2,r_hid,'西药类',1,0,now()),(2,r_hid,'器械类',1,0,now()),
(4,r_hid,'塑形镜类',1,0,now()),(4,r_hid,'RGP类',1,0,now()),(4,r_hid,'离焦软镜类',1,0,now()),
(5,r_hid,'到店训练类',1,0,now()),(5,r_hid,'家庭训练类',1,0,now()),
(6,r_hid,'护理液类',1,0,now()),(6,r_hid,'润眼液类',1,0,now()),(6,r_hid,'清洗仪类',1,0,now());
 END  IF;
  

 FETCH  cur_hid INTO r_hid;  

 UNTIL  no_results = 1  

 END REPEAT;  

 CLOSE  cur_hid;  /*Finally: cursor need be closed 用完后记得用CLOSE把资源释放掉*/  

 /* SELECT *  FROM infologs;  

 DROP TABLE  infologs; 
 
 SELECT *  FROM infologs1;  

 DROP TABLE  infologs1; 
 
 SELECT *  FROM infologs2;  

 DROP TABLE  infologs2; */ 

END // 

DELIMITER ; 



call `test` (); /*执行存储过程*/ 

　　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。

 

例子2：

DROP PROCEDURE if EXISTS updateExpireDate;
CREATE PROCEDURE updateExpireDate ()
BEGIN
	DECLARE r_hid INT (11);

	DECLARE expireDate date;

	#声明终止变量
	DECLARE
		not_result INT DEFAULT 0;

	#创建游标
	DECLARE
		cur_data CURSOR FOR SELECT h.hid
		,u.expire_date
		FROM
			hospital h
		LEFT JOIN `user` u ON h.hid = u.hid
		AND u.role = 'SALER'
		AND DATE_FORMAT(h.expire_date, '%Y-%m-%d') != DATE_FORMAT(u.expire_date, '%Y-%m-%d')
		WHERE
			h.`status` = 0;

	#必须在声明游标之后声明
	DECLARE CONTINUE HANDLER FOR NOT FOUND SET not_result = 1;

	#打开游标
	OPEN cur_data;

		FETCH cur_data INTO r_hid,expireDate;

		#遍历游标
		REPEAT

			IF r_hid IS NOT NULL THEN
				UPDATE hospital SET expire_date = expireDate WHERE hid = r_hid;
			END
			IF;

			FETCH cur_data INTO r_hid,expireDate;

			UNTIL not_result = 1
			END
		REPEAT;

	CLOSE cur_data;

END;

　　例子3：使用loop遍历游标

drop PROCEDURE if EXISTS test;
create PROCEDURE test()
BEGIN

		DECLARE  oid1  varchar(11);
		DECLARE  age1  varchar(32);
		DECLARE done INT DEFAULT FALSE;
		
		DECLARE cur_birth CURSOR FOR select oid,age from okjing_prod.order where birth is null;
		
		DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
		
		OPEN  cur_birth;     
		
		read_loop: LOOP
				
				FETCH  cur_birth INTO oid1,age1;
				IF done THEN
					LEAVE read_loop;
				 END IF;
			update okjing_prod.order set birth=date_sub(CURDATE(),INTERVAL age1 YEAR) where oid = oid1;
		END LOOP;
		CLOSE cur_birth;

END

　　

 注意：自定义的变量不要和数据库中的字段名一样，不然使用navicat运行时无效果

详解请参考：https://blog.csdn.net/pang_da_xing/article/details/53836235