sy6_3_1.sql

关于SQL数据库的实验代码和程序及一些函数的应用

create function fun_checkno(@pno char(6))
    returns integer as
    begin
        declare @num int
        if exists (select no from person
                     where no=@pno)
                     select @num=0
        else
              select @num=-1
        return @num
    end