if exists(select * from sysobjects where name='checkUser' and type='P')
begin
    drop procedure checkUser
end
go

CREATE PROCEDURE checkUser
@UserName nvarchar(50),
@Password nvarchar(50),
@ret int output
AS
set @ret = -1
if exists(SELECT * FROM mis.users
WHERE userName=@UserName AND userID=@Password )
begin
    set @ret = 0
end

return @ret
go
declare @ret int
exec checkUser '李一','19',@ret out
print @ret
go