如何使用IN参数创建MySQL存储过程?
为了使其理解,我们使用名为“student_info”的表,该表具有以下值-
mysql> Select * from student_info; +-----+---------+------------+------------+ | id | Name | Address | Subject | +-----+---------+------------+------------+ | 101 | YashPal | Amritsar | History | | 105 | Gaurav | Jaipur | Literature | | 110 | Rahul | Chandigarh | History | | 125 | Raman | Shimla | Computers | +------+--------+------------+------------+ 4 rows in set (0.00 sec)
现在,借助以下查询,我们将创建一个带有IN参数的存储过程,该存储过程将通过提供名称作为参数来显示特定学生的所有详细信息。
mysql> DELIMITER // ; mysql> Create PROCEDURE detail(IN S_Name VARCHAR(20)) -> BEGIN -> SELECT * From Student_info WHERE Name = S_Name; -> END // mysql> DELIMITER ;
S_Name是存储过程“详细信息”的IN参数。如果我们想查看学生姓名'Gaurav'的所有详细信息,则可以在以下查询的帮助下完成-
mysql> CALL detail('Gaurav'); +-----+--------+---------+------------+ | id | Name | Address | Subject | +-----+--------+---------+------------+ | 105 | Gaurav | Jaipur | Literature | +-----+--------+---------+------------+ 1 row in set (0.00 sec) mysql> CALL detail('Raman'); +-----+-------+---------+-----------+ | id | Name | Address | Subject | +-----+-------+---------+-----------+ | 125 | Raman | Shimla | Computers | +-----+-------+---------+-----------+ 1 row in set (0.00 sec)