使用存储过程和游标

将user表的数据转移到new_user表

#将user表所有数据转移到new_user表中 

DROP PROCEDURE IF EXISTS cursor_test;
DELIMITER $ 
CREATE PROCEDURE cursor_test()
BEGIN 
#声明user表存在的所有字段
 DECLARE user_id INT;
 DECLARE user_code VARCHAR(32);
 DECLARE NAME VARCHAR(32);
 DECLARE username VARCHAR(100);
 DECLARE PASSWORD VARCHAR(100);
 DECLARE organization_id INT;
 DECLARE STATUS CHAR(1);
 DECLARE telephone VARCHAR(100);
 DECLARE remark VARCHAR(100);
 DECLARE is_delete CHAR(1);
 
 #声明user所有数据的数量,用于遍历的计数 记得要加()不然报错
 DECLARE number INT DEFAULT (SELECT COUNT(*) FROM USER); 
 #声明游标 user_result
 DECLARE user_result CURSOR FOR SELECT * FROM USER;
 
 #开启游标
 OPEN user_result;
 WHILE number>0 DO 
   #获取游标中一条数据
   #注意:原表user中有的字段必须全部into去，不然掉用存储过程的时候会存在Incorrect number of FETCH variables错误
   FETCH user_result INTO user_id,user_code,NAME,username,PASSWORD,organization_id,STATUS,telephone,remark,is_delete;
   #插入语句
   INSERT INTO new_user (`user_id`, `user_code`, `name`, `username`, `password`,  `telephone`) 
   VALUES (user_id, user_code, NAME, username, PASSWORD,  telephone);
 SET number = number-1;
 END WHILE;
 #关闭游标
 CLOSE user_result; 
 END $
 
 DELIMITER;

创建new_user表

#创建需要转移数据的表new_user
DROP TABLE IF EXISTS new_user;
CREATE TABLE `new_user` (
    `user_id` INT (11),
    `user_code` VARCHAR (100),
    `name` VARCHAR (100),
    `username` VARCHAR (100),
    `password` VARCHAR (100),
    `telephone` VARCHAR (11)
); 

执行

#调用存储过程cursor_test
CALL cursor_test;
#查询新表new_user
SELECT * FROM new_user;