select from case statement

Question

Я борюсь с запросом, и я не знаю, в чем проблема. Мне нужно рассчитать финансовый год на основе APPROVAL_PERIOD, но APPROVAL_PERIOD рассчитан в заявлении CASE WHEN.

CASE WHEN DD.STATUS_CODE ='Denied' THEN 
      CASE WHEN CHK.MAXTRAILDATE BETWEEN '2015-05-22 00:00:00.0000000' AND '2015-05-31 00:00:00.0000000' THEN '201506' 
       ELSE 
       (CONVERT(CHAR(4),CHK.MAXTRAILDATE, 120) +''+SUBSTRING(CONVERT(nvarchar(6),CHK.MAXTRAILDATE, 112),5,2)) 
      END 
     ELSE 
      CASE WHEN DD.APPROVAL_DATE BETWEEN '2015-05-22 00:00:00.0000000' AND '2015-05-31 00:00:00.0000000' THEN '201506' 
       ELSE 
       (CONVERT(CHAR(4),DD.APPROVAL_DATE, 120) +''+SUBSTRING(CONVERT(nvarchar(6),DD.APPROVAL_DATE, 112),5,2)) 
      END 
END AS APPROVAL_PERIOD, 
    CASE 
WHEN APPROVAL_DATE between '2004-10-01 00:00:00.000' and '2005-09-30 23:59:00.000' THEN 'FY05' 
WHEN APPROVAL_DATE between '2005-10-01 00:00:00.000' and '2006-09-30 23:59:00.000' THEN 'FY06' 
WHEN APPROVAL_DATE between '2006-10-01 00:00:00.000' and '2007-09-30 23:59:00.000' THEN 'FY07' 
WHEN APPROVAL_DATE between '2007-10-01 00:00:00.000' and '2008-09-28 23:59:00.000' THEN 'FY08' 
WHEN APPROVAL_DATE between '2008-09-29 00:00:00.000' and '2009-09-30 23:59:00.000' THEN 'FY09' 
WHEN APPROVAL_DATE between '2009-10-01 00:00:00.000' and '2010-09-30 23:59:59.000' THEN 'FY10' 
WHEN APPROVAL_DATE between '2010-10-01 00:00:00.000' and '2011-09-30 23:59:59.000' THEN 'FY11' 
WHEN APPROVAL_DATE between '2011-10-01 00:00:00.000' and '2012-09-30 23:59:59.000' THEN 'FY12' 
WHEN APPROVAL_DATE between '2012-10-01 00:00:00.000' and '2013-09-30 23:59:59.000' THEN 'FY13' 
WHEN APPROVAL_DATE between '2013-10-01 00:00:00.000' and '2014-09-30 23:59:59.000' THEN 'FY14' 
WHEN APPROVAL_DATE between '2014-10-01 00:00:00.000' and '2015-09-30 23:59:59.000' THEN 'FY15' 
WHEN APPROVAL_DATE between '2015-10-01 00:00:00.000' and '2016-09-30 23:59:59.000' THEN 'FY16' 
WHEN APPROVAL_DATE between '2016-10-01 00:00:00.000' and '2017-09-30 23:59:59.000' THEN 'FY17' 
WHEN APPROVAL_DATE between '2017-10-01 00:00:00.000' and '2018-09-30 23:59:59.000' THEN 'FY18' 
WHEN APPROVAL_DATE between '2018-10-01 00:00:00.000' and '2019-09-30 23:59:59.000' THEN 'FY19' 
WHEN APPROVAL_DATE between '2019-10-01 00:00:00.000' and '2020-09-30 23:59:59.000' THEN 'FY20' 
WHEN APPROVAL_DATE between '2020-10-01 00:00:00.000' and '2021-09-30 23:59:59.000' THEN 'FY21' 
WHEN APPROVAL_DATE between '2021-10-01 00:00:00.000' and '2022-09-30 23:59:59.000' THEN 'FY22' 
ELSE ' ' 
END AS FY 
FROM table 

Я вычислил FY на основе APPROVAL DATE, но мне нужно, чтобы вычислить его на основе APPROVAL_PERIOD. Есть ли способ сделать это?

Answer 1

Просто пример того, как использовать динамическую переменную MySQL в запросе:

http://sqlfiddle.com/#!9/9eecb7d/24641

SELECT 
case when 1 then @var := 'one' else @var := 'two' end field1, 
case when @var ='one' then 'two' else 'three' end field2 

UPDATE В вашем случае это будет нечто вроде

CASE WHEN DD.STATUS_CODE ='Denied' THEN 
      CASE WHEN CHK.MAXTRAILDATE BETWEEN '2015-05-22 00:00:00.0000000' AND '2015-05-31 00:00:00.0000000' THEN @var := '201506' 
       ELSE 
       @var := (CONVERT(CHAR(4),CHK.MAXTRAILDATE, 120) +''+SUBSTRING(CONVERT(nvarchar(6),CHK.MAXTRAILDATE, 112),5,2)) 
      END 
     ELSE 
      CASE WHEN DD.APPROVAL_DATE BETWEEN '2015-05-22 00:00:00.0000000' AND '2015-05-31 00:00:00.0000000' THEN @var := '201506' 
       ELSE 
       @var := (CONVERT(CHAR(4),DD.APPROVAL_DATE, 120) +''+SUBSTRING(CONVERT(nvarchar(6),DD.APPROVAL_DATE, 112),5,2)) 
      END 
END AS APPROVAL_PERIOD, 
    CASE 
WHEN @var between '2004-10-01 00:00:00.000' and '2005-09-30 23:59:00.000' THEN 'FY05' 
WHEN @var between '2005-10-01 00:00:00.000' and '2006-09-30 23:59:00.000' THEN 'FY06' 
WHEN @var between '2006-10-01 00:00:00.000' and '2007-09-30 23:59:00.000' THEN 'FY07' 
WHEN @var between '2007-10-01 00:00:00.000' and '2008-09-28 23:59:00.000' THEN 'FY08' 
WHEN @var between '2008-09-29 00:00:00.000' and '2009-09-30 23:59:00.000' THEN 'FY09' 
WHEN @var between '2009-10-01 00:00:00.000' and '2010-09-30 23:59:59.000' THEN 'FY10' 
WHEN @var between '2010-10-01 00:00:00.000' and '2011-09-30 23:59:59.000' THEN 'FY11' 
WHEN @var between '2011-10-01 00:00:00.000' and '2012-09-30 23:59:59.000' THEN 'FY12' 
WHEN @var between '2012-10-01 00:00:00.000' and '2013-09-30 23:59:59.000' THEN 'FY13' 
WHEN @var between '2013-10-01 00:00:00.000' and '2014-09-30 23:59:59.000' THEN 'FY14' 
WHEN @var between '2014-10-01 00:00:00.000' and '2015-09-30 23:59:59.000' THEN 'FY15' 
WHEN @var between '2015-10-01 00:00:00.000' and '2016-09-30 23:59:59.000' THEN 'FY16' 
WHEN @var between '2016-10-01 00:00:00.000' and '2017-09-30 23:59:59.000' THEN 'FY17' 
WHEN @var between '2017-10-01 00:00:00.000' and '2018-09-30 23:59:59.000' THEN 'FY18' 
WHEN @var between '2018-10-01 00:00:00.000' and '2019-09-30 23:59:59.000' THEN 'FY19' 
WHEN @var between '2019-10-01 00:00:00.000' and '2020-09-30 23:59:59.000' THEN 'FY20' 
WHEN @var between '2020-10-01 00:00:00.000' and '2021-09-30 23:59:59.000' THEN 'FY21' 
WHEN @var between '2021-10-01 00:00:00.000' and '2022-09-30 23:59:59.000' THEN 'FY22' 
ELSE ' ' 
END AS FY 
FROM table 

Вы очень приветствуется, если возникнут вопросы