由於您無法使用窗口子句或按PERCENTILE_CONT(boo!)中的列按其他順序添加,因此以下是實現您的目標的一種方法。注:它並不漂亮,我相信它不會很棒,但至少應該起作用!
WITH mytable AS (SELECT 100 ID, '2017M01' mperiod, to_date('01/01/2017', 'dd/mm/yyyy') frdate, 60 fr FROM dual UNION ALL
SELECT 101 ID, '2017M01' mperiod, to_date('02/01/2017', 'dd/mm/yyyy') frdate, 75 fr FROM dual UNION ALL
SELECT 103 ID, '2017M01' mperiod, to_date('08/01/2017', 'dd/mm/yyyy') frdate, 48 fr FROM dual UNION ALL
SELECT 104 ID, '2017M02' mperiod, to_date('06/02/2017', 'dd/mm/yyyy') frdate, 55 fr FROM dual UNION ALL
SELECT 105 ID, '2017M02' mperiod, to_date('15/02/2017', 'dd/mm/yyyy') frdate, 63 fr FROM dual UNION ALL
SELECT 106 ID, '2017M03' mperiod, to_date('18/03/2017', 'dd/mm/yyyy') frdate, 41 fr FROM dual UNION ALL
SELECT 107 ID, '2017M03' mperiod, to_date('22/03/2017', 'dd/mm/yyyy') frdate, 71 fr FROM dual UNION ALL
SELECT 108 ID, '2016M12' mperiod, to_date('22/12/2016', 'dd/mm/yyyy') frdate, 42 fr FROM dual UNION ALL
SELECT 109 ID, '2016M11' mperiod, to_date('22/11/2016', 'dd/mm/yyyy') frdate, 32 fr FROM dual),
unpckd AS (SELECT mt.ID,
mt.mperiod,
mt.frdate,
mt.fr,
CASE WHEN substr(mt.mperiod, -2) <= d.id THEN SUBSTR(mt.mperiod, 1, 5) || to_char(d.id, 'fm09')
END new_mperiod,
d.id dummy_id
FROM mytable mt
INNER JOIN (SELECT LEVEL ID
FROM dual
CONNECT BY LEVEL <= 12) d ON substr(mt.mperiod, -2) <= d.id),
res AS (SELECT mperiod,
new_mperiod,
ROUND(PERCENTILE_CONT(0.8) WITHIN GROUP (ORDER BY fr) OVER (PARTITION BY CASE WHEN mperiod = new_mperiod THEN mperiod END),2) fr_80,
ROUND(PERCENTILE_CONT(0.8) WITHIN GROUP (ORDER BY fr) OVER (PARTITION BY new_mperiod),2) fr_80_ytd
FROM unpckd)
SELECT DISTINCT new_mperiod mperiod,
fr_80 "80%_FR",
fr_80_ytd "80%_FR_YtD"
FROM res
WHERE new_mperiod = mperiod
ORDER BY 1;
MPERIOD 80%_FR 80%_FR_YtD
-------- ---------- ----------
2016M11 32 32
2016M12 42 40
2017M01 69 69
2017M02 61.4 65.4
2017M03 65 69.4
這是通過在數字1到12(一年中的12個月)和mperiod的最後兩位數之間進行部分交叉連接而實現的。一旦我們有了,我們現在知道這些行所屬的整個ytd時期(例如,1號將匹配2017M01,2匹配2017M01和2017M02等),因此您現在可以爲此計算值生成一個標籤(我稱之爲new_mperiod)並使用它進行分區。
這顯然是效率低下的(因爲部分交叉連接會產生比一年中所不需要的數據所需的更多的行,這些數據在所有月份都沒有獲取,後來被濾除掉了,但我無法想象得更好這樣做的方式。