sql server 2000存储过程 _数据库技巧

if exists(select name from sysobjects where name=GetRecord and type = p)
   drop procedure GetRecord
GO

create procedure GetRecord
@id int output,              –输出p_id和p_path
@path nvarchar(255) output
as

select top 1 @id = p_id, @path = p_path from n_project where p_flag = 0;
if(@id > 0)  
   Update n_project set p_flag = 1 where p_id = @id
else
  begin
    set @id = 0;      –若没有结果则给个默认值，否则直接返回NULL会使程序错误
    set @path = ;  –若p_path为NULL，则它也会返回NULL，从而造成程序错误
  end
if(@path is NULL)
begin
   set @path = ;
end

if @@error=0
print Good
else
print Fail
go

–测试程序
declare @idd int
declare @ppath nvarchar(255)
EXEC dbo.GetRecord @idd output,@ppath output
select 1=@idd, 2=@ppath
go

SQL SERVER中，按CTR+0，即可输入空值NULL
http://blog.csdn.net/gzq400/archive/2007/02/02/1501235.aspx