MySQL--带有out的存储过程

带有out 的存储过程，同样可以返回一个值，也可以返回多个值

下面分别进行介绍

案例一：根据女神名，返回对应的男神名

delimiter $
create PROCEDURE myp7(in beautyName VARCHAR(20),out boyName VARCHAR(20))
begin 
        select bo.boyName into boyName
        from boys bo
        INNER JOIN beauty b on bo.id=b.boyfriend_id
        where b.name=beautyName;
end $
#调用
#set @bName$  #其实这个定义用户变量过程是不用写的，直接按照下面调用的写法就行
call myp7('小昭',@bName)$
select @bName$

这里我要强调一点就是，在使用dos窗口执行存储过程的时候，我的电脑也不知道是怎么搞的，始终不能粘贴内容，有时候及时粘贴进去内容之后，回车执行的时候，总是出现mysql->   就好像还让你输入下一行了。这里，我推荐大家使用navicat,在navicat中打开命令执行窗口，同样能够看到我们想要的效果，同时我们也不用再手动的设置字符集的编码格式了，方便多了。

下面是运行结果：

 案例二：根据女神名，返回对应的男神名和魅力值

delimiter $
create PROCEDURE     myp8(in beautyName VARCHAR(20),out boyName VARCHAR(20),out userCP INT)
begin
        select bo.boyName,bo.userCP into boyName,userCP
        from boys bo
        INNER JOIN beauty b on bo.id=b.boyfriend_id
        where b.name=beautyName;
end $

#调用
call myp7('小昭',@bName)$
select @bName，@userCP$

运行结果：

mysql> delimiter $
create PROCEDURE     myp8(in beautyName VARCHAR(20),out boyName VARCHAR(20),out userCP INT)
begin
        select bo.boyName,bo.userCP into boyName,userCP
        from boys bo
        INNER JOIN beauty b on bo.id=b.boyfriend_id
        where b.name=beautyName;
end $
Query OK, 0 rows affected (0.00 sec)
mysql> call myp7('小昭',@bName)$
Query OK, 1 row affected (0.00 sec)

mysql> select @bName$,@userCP$
+--------+
| @bName |
+--------+
| 张无忌 |
+--------+
1 row in set (0.06 sec)

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '@userCP' at line 1
mysql> call myp7('小昭',@bName,@userCP)$
1318 - Incorrect number of arguments for PROCEDURE girls.myp7; expected 2, got 3
mysql> call myp8('小昭',@bName,@userCP)$
Query OK, 1 row affected (0.00 sec)
mysql> select @bName$,@userCP$
+--------+
| @bName |
+--------+
| 张无忌 |
+--------+
1 row in set (0.05 sec)

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '@userCP' at line 1
mysql> SELECT @userCP$
+---------+
| @userCP |
+---------+
|     100 |
+---------+
1 row in set (0.06 sec)

mysql> SELECT @bName,@userCP$
+--------+---------+
| @bName | @userCP |
+--------+---------+
| 张无忌 |     100 |
+--------+---------+
1 row in set (0.06 sec)

mysql>