生成日期范围之间的日期
我需要填充一个表格来存储两个给定日期之间的日期范围:09/01/11 - 10/10/11
I need to populate a table that will store the date ranges between 2 given dates: 09/01/11 - 10/10/11
所以在这种情况下,表格将从 2011 年 9 月 1 日开始并每天存储到 11 年 10 月 10 日我想知道在 SQL Server 中是否有一种巧妙的方法来执行此操作 - 我目前正在使用 SQL Server 2008.谢谢
So in this case the table would start from 09/01/11 and store each day till it got to 10/10/11 I was wondering if there was a slick way of doing this in SQL Server - I am currently using SQL Server 2008. Thanks
推荐答案
Easy on SQL 2005+;如果您有数字或计数表,则更容易.我在下面伪造了它:
Easy on SQL 2005+; easier if you have a numbers or tally table. I faked it below:
DECLARE @StartDate DATE = '20110901'
, @EndDate DATE = '20111001'
SELECT DATEADD(DAY, nbr - 1, @StartDate)
FROM ( SELECT ROW_NUMBER() OVER ( ORDER BY c.object_id ) AS nbr
FROM sys.columns c
) nbrs
WHERE nbr - 1 <= DATEDIFF(DAY, @StartDate, @EndDate)
如果您有一个计数表,请将子查询替换为该表.没有递归.
If you have a tally table, replace the subquery with the table. No recursion.
由于人们似乎对计数表有疑问,让我用一个从零开始的计数表重写它.首先,这里有一些创建和填充表格的代码.
Since folks seem to have questions about the tally table, let me rewrite this using a zero-based tally table. First, here's some code to create and populate a table.
CREATE TABLE [dbo].[nbrs](
[nbr] [INT] NOT NULL
) ON [PRIMARY]
GO
CREATE UNIQUE CLUSTERED INDEX [clidx] ON [dbo].[nbrs]
(
[nbr] ASC
)
GO
INSERT INTO dbo.nbrs (nbr)
SELECT nbr-1
FROM ( SELECT ROW_NUMBER() OVER ( ORDER BY c.object_id ) AS nbr
FROM sys.columns c
) nbrs
GO
现在,您已将 numbers 表作为数据库中的永久对象,您可以将其重用于子查询的 INSTEAD 查询.该查询也已被编辑为使用从零开始的计算.
Now, that you have the numbers table as a permanent object in your database, you can reuse it for the query INSTEAD of the subquery. The query has also been edited to use a zero-based calculation.
DECLARE @StartDate DATE = '20110901'
, @EndDate DATE = '20111001'
SELECT DATEADD(DAY, nbr, @DateStart)
FROM nbrs
WHERE nbr <= DATEDIFF(DAY, @DateStart, @DateEnd)
高性能,无递归.
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