存储过程定义如下:
CREATE PROCEDURE CAL_GPA
@SNO CHAR(7),
@GPA DEC(2,0) OUTPUT
AS
BEGIN
declare @GP4 DEC(2,0),@GP3 DEC(2,0),@GP2 DEC(2,0),@GP1 DEC(2,0);
SET @GP4=(SELECT SUM(4*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=85));
SET @GP3=(SELECT SUM(3*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=75 AND SC.GRADE<85));
SET @GP2=(SELECT SUM(2*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=60 AND SC.GRADE<75));
SET @GP1=(SELECT SUM(CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE<60));
SET @GPA=(@GP4)+(@GP3)+(@GP2)+(@GP1);
IF @@rowcount=0
BEGIN
raiserror('error',16,1)
rollback transaction
END
END
GO


调用语句如下:
declare @GPA DEC(4,1)
execute CAL_GPA '0309203',@GPA OUTPUT
print @GPA



但是最后并没有输出GPA,请教错在哪

declare @GP DEC(2,0)
execute CAL_GPA @SNO＝'0309203',@GPA＝@GP OUTPUT
print @GP

也是没有输出啊
怎么办啊?

SP改成
CREATE PROCEDURE CAL_GPA
@SNO CHAR(7)
AS
BEGIN
declare @GP4 DEC(2,0),@GP3 DEC(2,0),@GP2 DEC(2,0),@GP1 DEC(2,0);
SET @GP4=(SELECT SUM(4*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=85));
SET @GP3=(SELECT SUM(3*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=75 AND SC.GRADE<85));
SET @GP2=(SELECT SUM(2*CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE>=60 AND SC.GRADE<75));
SET @GP1=(SELECT SUM(CREDIT)/SUM(CREDIT) FROM Courses WHERE Courses.CNO IN (SELECT SC.CNO FROM SC WHERE SC.SNO=@SNO AND SC.GRADE<60));
SELECT (@GP4)+(@GP3)+(@GP2)+(@GP1) AS N'GPA';
IF @@rowcount=0
BEGIN
raiserror('error',16,1)
rollback transaction
END
END
GO


用execute CAL_GPA '0309203'调结果试试

[此贴子已经被作者于2006-4-8 11:02:50编辑过]

这样调以后显示一个表格,然后GPA为NULL,还是不对啊

为Null？

'0309203'这个值没有问题吧。

[此贴子已经被作者于2006-4-8 20:19:25编辑过]

这个值没问题,数据库中有3条这个学号的成绩记录的

好象我写的存储过程的语法是没问题的吧?
@GPA=(@GP1)+(@GP2)+.....这样加是可以的吧?

你中间插几个debug点执行一下，看哪个值出了问题

怎么插?这些语法不会哦