将列的值存储到MySQL存储过程的变量中
要声明变量，请在MySQL存储过程中使用DECLARE。让我们首先创建一个表-
mysql> create table DemoTable2034 -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentName varchar(20), -> StudentAge int -> );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable2034(StudentName,StudentAge) values('Chris',23);
mysql> insert into DemoTable2034(StudentName,StudentAge) values('David',21);
mysql> insert into DemoTable2034(StudentName,StudentAge) values('Robert',25);
mysql> insert into DemoTable2034(StudentName,StudentAge) values('Mike',19);使用select语句显示表中的所有记录-
mysql> select *from DemoTable2034;
这将产生以下输出-
+-----------+-------------+------------+ | StudentId | StudentName | StudentAge | +-----------+-------------+------------+ | 1 | Chris | 23 | | 2 | David | 21 | | 3 | Robert | 25 | | 4 | Mike | 19 | +-----------+-------------+------------+ 4 rows in set (0.00 sec)
这是创建存储过程并将上述表的列值存储在存储过程变量中的查询-
mysql> delimiter //
mysql> create procedure select_into_variable(id int)
-> begin
-> declare name varchar(50);
-> select StudentName into name from DemoTable2034 where StudentId=id;
-> select concat('Your Name is= ',name);
-> end
-> //
mysql> delimiter ;调用存储过程-
mysql> call select_into_variable(4);
这将产生以下输出-
+-------------------------------+
| concat('Your Name is= ',name) |
+-------------------------------+
| Your Name is= Mike |
+-------------------------------+
1 row in set (0.04 sec)