如何在 Oracle SQL 中的键中的特定值之后的行中添加标志？

Question

我有以下数据：

Key Stage CreateDate
AAF 0     01-Jan-2018
AAF 0     02-Jan-2018
AAF 0     10-Jan-2018
AAF 20    20-Jan-2018
AAF 40    20-Mar-2018
AAF 0     01-May-2018
AAF 0     10-May-2018
AAF 0     20-May-2018
AAF 30    20-Jun-2018
AAF 0     20-Jul-2018   
AAF 100   20-Jul-2018

我基本上是在尝试计算每个阶段花费的天数。我目前在每个阶段取最小日期，并找出下一阶段的最小日期之间的差异：

select 
key,
stage,
cast(extract (day from max(next_dt) - min(createddate)) as number) as interval_days
from
(
select 
key,
stage,
createddate
lead(createddate,1) over (partition by  key order by createddate) next_dt
from  oppstages
)
group by key,stage

可以看出，有时阶段从 0-40 前进，但又回到 0。所以上面的逻辑不能正常工作，我认为有必要将 0-40 分组为一个类别，40 之后的任何内容作为下一类别，依此类推（如果阶段减少并以新的较小阶段编号重新开始）。下面的查询给出了概率下降的点，但我无法标记以进一步对行进行分组。

select key,
stage,
createddate, 
next_dt,
next_prob,
case when   next_prob < stage  then 1   else 0 end as valid_flag,
from 
(
select 
key,
stage,
createddate,
lead(createddate,1) over (partition by  key order by createddate) next_dt, 
coalesce(lead(stage,1) over (partition by  key order by createddate),101) next_prob, 
from oppstages
) a

我期待此输出，以便我可以使用标志进行分组来计算在每个实例上花费的天数：

Key Stage CreateDate    Flag
AAF 0     01-Jan-2018   1
AAF 0     02-Jan-2018   1
AAF 0     10-Jan-2018   1
AAF 20    20-Jan-2018   1
AAF 40    20-Mar-2018   1
AAF 0     01-May-2018   2
AAF 0     10-May-2018   2
AAF 0     20-May-2018   2
AAF 30    20-Jun-2018   2
AAF 10     20-Jul-2018   3
AAF 100   20-Jul-2018   3

谢谢。

Answer 1

您可以尝试使用 lag window 函数获取 Stage 之前的值。

然后使用CASE WHEN检查PREVAL > STAGE做增加1。

CREATE TABLE T(
  Key varchar(50),
  Stage int,
  CreateDate date
);



INSERT INTO T VALUES ('AAF',0,TO_DATE('01-01-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',0,TO_DATE('02-01-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',0,TO_DATE('10-01-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',20,TO_DATE('20-01-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',40,TO_DATE('20-03-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',0,TO_DATE('01-05-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',0,TO_DATE('10-05-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',0,TO_DATE('20-05-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',30,TO_DATE('20-06-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',10,TO_DATE('20-07-2018','dd-mm-yyyy'));  
INSERT INTO T VALUES ('AAF',100,TO_DATE('20-07-2018','dd-mm-yyyy'));

查询 1:

SELECT t1.KEY,
       t1.STAGE,
      (SUM(CASE WHEN PREVAL > STAGE THEN 1 ELSE 0 END) over (partition by Key order by CreateDate) + 1)  Flag
FROM (
  SELECT T.*,lag(Stage) over (partition by Key  order by CreateDate) preVAL
  FROM T 
)t1

Results:

| KEY | STAGE | FLAG |
|-----|-------|------|
| AAF |     0 |    1 |
| AAF |     0 |    1 |
| AAF |     0 |    1 |
| AAF |    20 |    1 |
| AAF |    40 |    1 |
| AAF |     0 |    2 |
| AAF |     0 |    2 |
| AAF |     0 |    2 |
| AAF |    30 |    2 |
| AAF |    10 |    3 |
| AAF |   100 |    3 |

Answer 2

您遇到了间隙和孤岛问题。一个简单的解决方案是使用行号的差异。这定义了组。

select t.*, (seqnum_2 - seqnum_1) as grp
from (select os.*,
             row_number() over (partition by key order by createdate) as seqnum,
             row_number() over (partition by key, stage order by createdate) as seqnum_2
      from oppstages os
     ) os;

您可能想要的是聚合：

select key, stage, min(createdate), max(createdate),
       lead(min(createdate)) over (partition by key, stage, seqnum - seqnum_2 order by createdate) as next_creatdate
from (select os.*,
             row_number() over (partition by key order by createdate) as seqnum,
             row_number() over (partition by key, stage order by createdate) as seqnum_2
      from oppstages os
     ) os
group by key, stage, (seqnum_2 - seqnum)

我不确定你想要什么逻辑，但这应该有你需要的所有信息。

如何在 Oracle SQL 中的键中的特定值之后的行中添加标志？

How to add a flag to the rows after a specific value within a key in Oracle SQL?

sql

oracle

analytic-functions

lag

lead