如何基于yyyymmdd检索当年的月份和去年的同一个月

Question

is there a way I can retrieve the month this year and same month last year based on yyyymmdd? My report is comparing data from last year month and current year month. For example if yyyymmdd is 20180613 then I would like to have dates 20180601 to 20180613 and 20170601 to 20170613.

Would really appreciate all your advice and help I can get.

Thank you!

Answer 1

In Oracle -

Query -

select to_char(trunc(sysdate),'yyyymmdd') as y1, to_char(trunc(sysdate,'mm'),'yyyymmdd') as y2, to_char(trunc(sysdate) + interval '-1' year,'yyyymmdd') as y3, to_char(trunc(sysdate,'mm') + interval '-1' year,'yyyymmdd') as y4 from dual;

Output -

"Y1","Y2","Y3","Y4"
"20180613","20180601","20170613","20170601"

Answer 2

SQL Server

You can try Convert(type,datetime,112) and DATEADD

declare @tdate DATETIME= CONVERT(DATETIME, '20180613', 112) ;
select CONVERT(nvarchar(20), sDate1, 112) sDate1,
    CONVERT(nvarchar(20), eDate1, 112) eDate1,
    CONVERT(nvarchar(20), sDate2, 112) sDate2,
    CONVERT(nvarchar(20), eDate2, 112) eDate2
from (
    SELECT DATEADD(day, - DAY ( @tdate ) + 1 ,  @tdate) sDate1,
        @tdate eDate1,
        DATEADD(year,-1,DATEADD(day, - DAY ( @tdate ) + 1 ,  @tdate)) sDate2,
        DATEADD(year,-1,@tdate) eDate2
)T;

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Result:

sDate1               eDate1               sDate2               eDate2
-------------------- -------------------- -------------------- --------------------
20180601             20180613             20170601             20170613

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Test DEMO Link