create function gettopid
(@year char(5))
returns int
begin
declare @id int
select top 1 @id=书籍编号
from 定单 join 定单编号 on 定单.定单编号=定单细目.定单编号
where datepart(yyyy,日期)=@year
group by 书籍编号
order by sum(数量) desc
return(case when @@rowcount=0 then 0 else @id end)
end
(@year char(5))
returns int
begin
declare @id int
select top 1 @id=书籍编号
from 定单 join 定单编号 on 定单.定单编号=定单细目.定单编号
where datepart(yyyy,日期)=@year
group by 书籍编号
order by sum(数量) desc
return(case when @@rowcount=0 then 0 else @id end)
end
所以报错。
(@year char(5))
returns int
begin
declare @id int
declare @out int
select top 1 @id=书籍编号
from 定单 join 定单编号 on 定单.定单编号=定单细目.定单编号
where datepart(yyyy,日期)=@year
group by 书籍编号
order by sum(数量) desc
if @@rowcount=0
set @out = 0
else
set @out = @id
return @out
end