CREATE proc my_proc_UserLogin
@UserName varchar(50),@UserPass varchar(50),@MemberID int output
as
declare @ErrorNum int
set @ErrorNum=0
if exists(select * from tb_Member where Name=@UserName and Password=@UserPass)
begin
select MemberID from tb_Member where Name=@UserName and Password=@UserPass
end
else
begin
return @ErrorNum
end
这样写,当给出正确的用户名和密码,就能输出ID,
如果用户或密码不正确的话,什么也不返回,为什么?怎么不返回我设定的@ErrorNum呢?
@UserName varchar(50),@UserPass varchar(50),@MemberID int output
as
declare @ErrorNum int
set @ErrorNum=0
if exists(select * from tb_Member where Name=@UserName and Password=@UserPass)
begin
select MemberID from tb_Member where Name=@UserName and Password=@UserPass
end
else
begin
return @ErrorNum
end
这样写,当给出正确的用户名和密码,就能输出ID,
如果用户或密码不正确的话,什么也不返回,为什么?怎么不返回我设定的@ErrorNum呢?
EXECUTE my_proc_UserLogin ......select @@errornum使用 OUTPUT 参数
OUTPUT 参数允许外部过程、批处理或多条 Transact-SQL 语句访问在过程执行期间设置的某个值。下面的示例创建一个存储过程 (titles_sum),并使用一个可选的输入参数和一个输出参数。首先,创建过程:USE pubs
GO
IF EXISTS(SELECT name FROM sysobjects
WHERE name = 'titles_sum' AND type = 'P')
DROP PROCEDURE titles_sum
GO
USE pubs
GO
CREATE PROCEDURE titles_sum @@TITLE varchar(40) = '%', @@SUM money OUTPUT
AS
SELECT 'Title Name' = title
FROM titles
WHERE title LIKE @@TITLE
SELECT @@SUM = SUM(price)
FROM titles
WHERE title LIKE @@TITLE
GO接下来,将该 OUTPUT 参数用于控制流语言。 说明 OUTPUT 变量必须在创建表和使用该变量时都进行定义。
参数名和变量名不一定要匹配,不过数据类型和参数位置必须匹配(除非使用 @@SUM = variable 形式)。 DECLARE @@TOTALCOST money
EXECUTE titles_sum 'The%', @@TOTALCOST OUTPUT
IF @@TOTALCOST < 200
BEGIN
PRINT ' '
PRINT 'All of these titles can be purchased for less than $200.'
END
ELSE
SELECT 'The total cost of these titles is $'
+ RTRIM(CAST(@@TOTALCOST AS varchar(20)))下面是结果集:Title Name
------------------------------------------------------------------------
The Busy Executive's Database Guide
The Gourmet Microwave
The Psychology of Computer Cooking(3 row(s) affected)Warning, null value eliminated from aggregate.
All of these titles can be purchased for less than $200.
EXECUTE @ErrorNum = my_proc_UserLogin @UserName ,@UserPass,@MemberID
select @errornum
CREATE proc my_proc_UserLogin
@UserName varchar(50),@UserPass varchar(50),@MemberID int output
as
declare @ErrorNum int
set @ErrorNum=0
if exists(select * from tb_Member where Name=@UserName and Password=@UserPass)
begin
select MemberID from tb_Member where Name=@UserName and Password=@UserPass
end
else
begin
set @MemberID= @ErrorNum
end