Question

SQL Server中声明变量

为什么我所有变量都声明了，但系统说我没有？

Answer 1

SQL Server中声明变量
declare @a int
declare @b int
declare @c int
declare @d int
declare @str int
set @str=0
while @str<=9999
begin
set @a=cast(substring(right('0000'+cast(cast(@str as varchar) as varchar),4),1,1) as int)
set @b=cast(substring(right('0000'+cast(cast(@str as varchar) as varchar),4),2,1) as int)
set @c=cast(substring(right('0000'+cast(cast(@str as varchar) as varchar),4),3,1) as int)
set @d=cast(substring(right('0000'+cast(cast(@str as varchar) as varchar),4),4,1) as int)
if (@a*7+@b*9+@c*10+@d*5+222)%11=3
begin
print ('a='+cast(@a as varchar)+' b='+cast(@b as varchar)+' c='+cast(@c as varchar)+' d='+cast(@d as varchar))
end
set @str=@str+1
end

Answer 2

检查一下声明变量语句的位置，看对不对。