Sql 查询以获取最大月数的值之和

Oracle 11中的此查询获取过去1年的值之和，当有1年的数据时，此查询有效

当数据少于1年时，此查询返回0，而不是最早年份之前的值之和

例如，如果只有6个月的数据，则查询应返回到第6个月的值的总和

SELECT SUM (DECODE (rnk, 11, rt, 0)) 1Y
FROM (SELECT entity_id,rnk,
             SUM (ABS(NVL (value, 0))) OVER (PARTITION BY TRIM (entity_id) ORDER BY rnk) rt
      FROM (SELECT psm.*,RANK () OVER (PARTITION BY entity_id ORDER BY period_end_date DESC) AS rnk
            FROM myTable psm
            WHERE psm.entity_id = '1'
            ORDER BY period_end_date DESC
           ) rank_tab
      WHERE rnk < 12
      );

在上面的示例中，1Y应该返回1+2+3+4+5+6=21。 相反，我的查询返回0，因为它正在查找rnk=11，它不存在

SUM (DECODE (rnk, 11, rt, 0)) 1Y

多谢各位

SELECT 
CASE WHEN MRank < 11 then maxY else OneY end as lc_incearned_1Y
FROM (
WITH R as
(SELECT MAX(RNK) MaxRank FROM (
SELECT RANK () OVER (PARTITION BY TRIM (entity_id) ORDER BY period_end_date 
DESC) AS rnk FROM myTbl psm
WHERE TRIM (psm.entity_id) = '1' AND period_end_date < 
to_date('9/30/2019','MM/DD/YYYY')
ORDER BY period_end_date DESC))
select MAX(MaxRank) MRank,
SUM (DECODE (rnk, MaxRank, rt, 0)) maxY,
SUM (DECODE (rnk, 11, rt, 0)) OneY,  --13051.97
FROM (SELECT entity_id,rnk,
SUM (ABS (NVL (value, 0))) OVER (PARTITION BY TRIM (entity_id) ORDER BY rnk) rt
FROM (SELECT psm.*,RANK () OVER (PARTITION BY TRIM (entity_id) ORDER BY period_end_date DESC) AS rnk FROM CREF.PORTFOLIO_SUMM_MTHEND psm
WHERE TRIM (psm.entity_id) = '1' AND period_end_date < to_date('9/30/2019','MM/DD/YYYY')
ORDER BY period_end_date DESC) rank_tab WHERE rnk < 12) T,R)

编辑：

这很有效。但是，如果你知道更好的方法，请告诉我。多谢各位

SELECT 
CASE WHEN MRank < 11 then maxY else OneY end as lc_incearned_1Y
FROM (
WITH R as
(SELECT MAX(RNK) MaxRank FROM (
SELECT RANK () OVER (PARTITION BY TRIM (entity_id) ORDER BY period_end_date 
DESC) AS rnk FROM myTbl psm
WHERE TRIM (psm.entity_id) = '1' AND period_end_date < 
to_date('9/30/2019','MM/DD/YYYY')
ORDER BY period_end_date DESC))
select MAX(MaxRank) MRank,
SUM (DECODE (rnk, MaxRank, rt, 0)) maxY,
SUM (DECODE (rnk, 11, rt, 0)) OneY,  --13051.97
FROM (SELECT entity_id,rnk,
SUM (ABS (NVL (value, 0))) OVER (PARTITION BY TRIM (entity_id) ORDER BY rnk) rt
FROM (SELECT psm.*,RANK () OVER (PARTITION BY TRIM (entity_id) ORDER BY period_end_date DESC) AS rnk FROM CREF.PORTFOLIO_SUMM_MTHEND psm
WHERE TRIM (psm.entity_id) = '1' AND period_end_date < to_date('9/30/2019','MM/DD/YYYY')
ORDER BY period_end_date DESC) rank_tab WHERE rnk < 12) T,R)

---

似乎您需要将您的值从最近一段时间的结束日期加起来，直到十一个月范围内的最早日期。最好使用maxperiod\u end\u date over partition by entity\u id order by period\u end\u date desc分析函数以及当前秩函数。然后应用介于、期间、结束和日期之间的月份。如果您需要从当前日期开始查找，则去掉max分析函数，并在函数之间的月份用truncsysdate替换。因此，请使用：

with t as
(
select max(period_end_date) over (partition by entity_id order by period_end_date desc) as mx,
       rank() over (partition by entity_id order by period_end_date desc) as rnk,
       t.*
  from myTable t
)
select sum(nvl(value,0)) as sum_value
  from t
 where months_between(mx,period_end_date)<=11

---

样本数据和期望结果以及对逻辑的清晰解释都会有所帮助。我已经添加了样本数据和期望结果。@faujong，您只需要当前日期的最后11个月数据还是最后11行数据？您是否只是尝试了一个简单的求和而没有秩子查询？您可以将id和日期约束放在WHERE子句中。我需要过去11个月数据的总和。

with t as
(
select max(period_end_date) over (partition by entity_id order by period_end_date desc) as mx,
       rank() over (partition by entity_id order by period_end_date desc) as rnk,
       t.*
  from myTable t
)
select sum(nvl(value,0)) as sum_value
  from t
 where months_between(mx,period_end_date)<=11