按序列號分組時遇到的問題

Question

我基本上是在sql之後執行以下操作。我是在一系列連續的數字之後，與列B發生變化時相關，但是保持列ID依次爲 我嘗試過密集等級，但它總是拋出ID列的序列，這會破壞我之後的行爲。有任何想法嗎？

 
ID||A||B 
01||T||1 
02||T||1 
03||T||0 
04||T||0 
05||T||1 
06||T||1 
07||T||1 
08||T||0 
09||T||1 
10||T||1 
11||T||0 

INTO

 
ID||A||B||C 
01||T||1||1 
02||T||1||1 
03||T||0||2 
04||T||0||3 
05||T||1||4 
06||T||1||4 
07||T||1||4 
08||T||0||5 
09||T||1||6 
10||T||1||6 
11||T||0||7 

Answer 1

--#3: Running total of value changes 
select id, a, b 
    ,sum(has_changed) over (partition by A order by id 
     rows between unbounded preceding and current row) c 
from 
(
    --#2: Find rows where the value changed. 
    select id, a, b 
     ,case 
      when b = lag(b) over (partition by A order by id) then 0 
      else 1 
     end has_changed  
    from 
    (
     --#1: Test data 
     select '01' ID, 'T' A, 1 B from dual union all 
     select '02' ID, 'T' A, 1 B from dual union all 
     select '03' ID, 'T' A, 0 B from dual union all 
     select '04' ID, 'T' A, 0 B from dual union all 
     select '05' ID, 'T' A, 1 B from dual union all 
     select '06' ID, 'T' A, 1 B from dual union all 
     select '07' ID, 'T' A, 1 B from dual union all 
     select '08' ID, 'T' A, 0 B from dual union all 
     select '09' ID, 'T' A, 1 B from dual union all 
     select '10' ID, 'T' A, 1 B from dual union all 
     select '11' ID, 'T' A, 0 B from dual 
    ) test_data 
) 
order by id; 

結果：

ID A B C 
01 T 1 1 
02 T 1 1 
03 T 0 2 
04 T 0 2 
05 T 1 3 
06 T 1 3 
07 T 1 3 
08 T 0 4 
09 T 1 5 
10 T 1 5 
11 T 0 6 

不完全一樣，但我覺得你的例子有一個額外的增量，如@Adam霍克斯指出。

---

UPDATE

這將生成的預期結果：

--#3: Running total of value changes, or where the value is 0 
select id, a, b 
    ,sum(has_changed_or_0) over (partition by A order by id 
     rows between unbounded preceding and current row) c 
from 
(
    --#2: Find rows where the value changed, or where value is 0 
    select id, a, b 
     ,case 
      when b = 0 then 1 
      when b = lag(b) over (partition by A order by id) then 0 
      else 1 
     end has_changed_or_0 
    from 
    (
     --#1: Test data 
     select '01' ID, 'T' A, 1 B from dual union all 
     select '02' ID, 'T' A, 1 B from dual union all 
     select '03' ID, 'T' A, 0 B from dual union all 
     select '04' ID, 'T' A, 0 B from dual union all 
     select '05' ID, 'T' A, 1 B from dual union all 
     select '06' ID, 'T' A, 1 B from dual union all 
     select '07' ID, 'T' A, 1 B from dual union all 
     select '08' ID, 'T' A, 0 B from dual union all 
     select '09' ID, 'T' A, 1 B from dual union all 
     select '10' ID, 'T' A, 1 B from dual union all 
     select '11' ID, 'T' A, 0 B from dual 
    ) test_data 
) 
order by id;