日期的最后一次出现 [英] last occurence of date

问题描述

我需要找到日期的最后一次出现(在我的情况下是5月1日的静态日期)

I need to find the last occurence of a date (in my case a static date 1st of may)

我做到了这一点，但我知道可以用更聪明的方式完成

I made this which works but i know this can be done in a much smarter way

declare @lastmay date
set @lastmay = DATEADD(YY,YEAR(GETDATE())-2000,'20000501')
IF @lastmay <= GETDATE()
BEGIN
    SET @lastmay = DATEADD(YY,-1,@lastmay)
END

推荐答案

在SQL中使用日期时，对数据库中的Dates实用程序表进行比较是很有帮助的.

When you are working with dates in SQL it can be a real help to have a Dates utility table on your database that you can then compare against.

本文对此进行了很好的讨论: http://www.techrepublic.com/blog/datacenter/simplify-sql-server-2005-queries-with-a-dates-table/326

This article discusses it well: http://www.techrepublic.com/blog/datacenter/simplify-sql-server-2005-queries-with-a-dates-table/326

如果您实现了查询变得非常简单，例如(使用文章中的列)

If you implemented that your queries could become quite simple such as (using columns from article)

Declare @lastmay date

Select @lastmay = DateFull 
from DateLookup
    where MonthNumber = 5
    and MonthDay = 1
    and Datefull < getdate()

这篇关于日期的最后一次出现的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！