以下是一个存储过程,它从具有以下数据的表“student_info”的名称列中获取记录 -
mysql> Select * from Student_info; +-----+---------+------------+------------+ | id | Name | Address | Subject | +-----+---------+------------+------------+ | 101 | YashPal | Amritsar | History | | 105 | Gaurav | Chandigarh | Literature | | 125 | Raman | Shimla | Computers | | 127 | Ram | Jhansi | Computers | +-----+---------+------------+------------+ 4 rows in set (0.00 sec) mysql> Delimiter // mysql> CREATE PROCEDURE cursor_defined(OUT val VARCHAR(20)) -> BEGIN -> DECLARE a,b VARCHAR(20); -> DECLARE cur_1 CURSOR for SELECT Name from student_info; -> DECLARE CONTINUE HANDLER FOR NOT FOUND -> SET b = 1; -> OPEN CUR_1; -> REPEAT -> FETCH CUR_1 INTO a; -> UNTIL b = 1 -> END REPEAT; -> CLOSE CUR_1; -> SET val = a; -> END// Query OK, 0 rows affected (0.04 sec) mysql> Delimiter ; mysql> Call cursor_defined2(@val); Query OK, 0 rows affected (0.11 sec) mysql> Select @val; +------+ | @val | +------+ | Ram | +------+ 1 row in set (0.00 sec)
从上面的结果集中,我们可以看到 val 参数的值是“Ram”,因为它是“Name”列的最后一个值。
以上就是创建一个 MySQL 存储过程,使用游标从表中获取行?的详细内容,更多请关注php中文网其它相关文章!
每个人都需要一台速度更快、更稳定的 PC。随着时间的推移,垃圾文件、旧注册表数据和不必要的后台进程会占用资源并降低性能。幸运的是,许多工具可以让 Windows 保持平稳运行。
Copyright 2014-2025 https://www.php.cn/ All Rights Reserved | php.cn | 湘ICP备2023035733号