SQL日期计算问题

Question

--try:GO
CREATE FUNCTION fn_getDate
(
@p_Year SMALLINT,
@p_Month TINYINT,
@p_N     TINYINT
)
RETURNS SMALLDATETIME
AS
BEGIN
       declare @i int,@date  SMALLDATETIME
       select @date=convert(smalldatetime,rtrim(@p_Year)+'-'+rtrim(@p_Month)+'-1')
       set @i=(@p_N-1)*7
       while @i<@p_N*7
        begin
            if datepart(weekday,dateadd(day,@i,@date))=1
                begin
                     break
                end
            else
                set @i=@i+1
        end
  return dateadd(day,@i,@date)
 END
GO/*
select dbo.fn_getDate(2007,3,2)
---------------------------------
2007-03-11 00:00:00
*/

Answer 1

忘了,最好在之前對輸入的參數加以判斷
筆如@p_N between 1 and 5
 @p_Month between 1 and 12 ...