这个的最右边一列将计算1月前的任何日期的上一个星期日。我已经将其他栏目作为一种简单的方式来记录和实验逻辑。
没有分支逻辑,它都是纯日期数学,所以它应该合理快速地进行聚合,并且应该能够在日期列上使用索引。
DECLARE @Date DATE = '20170205';
SELECT SampleDate= @Date ,
PreviousLastSundayInJanuaryForSampleDate = DATEADD(DAY,(DATEPART(WEEKDAY,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH
,DATEADD(DAY,((DATEPART(DAYOFYEAR,DATEADD(DAY,(DATEPART(WEEKDAY,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))-1)*-1,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))))-1) * -1 ,@Date))-1)*-1
,DATEADD(DAY,((DATEPART(DAYOFYEAR,DATEADD(DAY,(DATEPART(WEEKDAY,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))-1)*-1,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))))-1) * -1 ,@Date))))-1)*-1,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH
,DATEADD(DAY,((DATEPART(DAYOFYEAR,DATEADD(DAY,(DATEPART(WEEKDAY,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))-1)*-1,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))))-1) * -1 ,@Date))-1)*-1
,DATEADD(DAY,((DATEPART(DAYOFYEAR,DATEADD(DAY,(DATEPART(WEEKDAY,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))-1)*-1,EOMONTH(DATEADD(MONTH,(DATEPART(MONTH,@Date)-1)*-1,@Date)))))-1) * -1 ,@Date))))
要在表中使用它,请将@Date替换为您自己的日期字段。
更新与样品结果:
SampleDate PreviousLastSundayInJanuaryForSampleDate
2008-06-03 2008-01-27
2008-12-20 2008-01-27
2009-07-08 2009-01-25
2010-01-24 2009-01-25
2010-08-12 2010-01-31
2011-02-28 2011-01-30
2011-09-16 2011-01-30
2012-04-03 2012-01-29
2012-10-20 2012-01-29
2013-05-08 2013-01-27
2013-11-24 2013-01-27
2014-06-12 2014-01-26
2014-12-29 2014-01-26
2015-07-17 2015-01-25
2016-02-02 2016-01-31
2016-08-20 2016-01-31
2017-03-08 2017-01-29
2017-09-24 2017-01-29
2018-04-12 2018-01-28
2018-10-29 2018-01-28
2019-05-17 2019-01-27
2019-12-03 2019-01-27
2020-06-20 2020-01-26
无论是日期部分或DATENAME功能将帮助您与此有关。 –
@ dan-bracuk你能否更新T-SQL代码并发送它们?这将是非常有益的。 – user2331670