Gaps and Islands 根据列序查询/重置行数

Question

我知道有很多这样的例子，但仍然找不到确切的解决方案。

我希望根据 1 和 0 的序列重置行计数。

DECLARE @TestTable TABLE (category INT, ts INT,window int)
INSERT INTO @TestTable (category,ts,window)
VALUES  (1,1,1),(1,2,1),(1,3,0),(1,4,0),(1,5,1),(1,6,1),(1,7,1),(2,1,0),(2,2,1),(2,3,1),(2,4,1),(2,5,0),(2,6,0),(2,7,1),(2,8,1),(2,9,1),(2,10,1),(2,11,1)

在上面的 table 中，我想要一个以 1 递增的行号列，按类别分区，但每次 window 更改时都需要重置计数。

到目前为止我最好的是：

SELECT
    x.category,
    ts,
    window, 
    is_group, 
    SUM( is_group ) OVER (PARTITION BY x.category ORDER BY ts ROWS BETWEEN 1 PRECEDING AND 0 FOLLOWING ) * is_group
FROM
    (
    SELECT 
        *, 
        CASE WHEN LAG(window) OVER(PARTITION BY category ORDER BY ts  ) = window THEN 1 ELSE 0 END is_group
    FROM @TestTable 
    ) x
ORDER BY x.category,ts

这几乎有效，但对于最后一段，它不会将行号增加超过 2:

Answer 1

是这样的吗？

DECLARE @TestTable TABLE (category INT, ts INT,window int)
INSERT INTO @TestTable (category,ts,window)
VALUES  (1,1,1),(1,2,1),(1,3,0),(1,4,0),(1,5,1),(1,6,1),(1,7,1),(2,1,0),(2,2,1),(2,3,1),(2,4,1),(2,5,0),(2,6,0),(2,7,1),(2,8,1),(2,9,1),(2,10,1),(2,11,1);


with ctex
as
(
SELECT
x.category,
ts,
window, 
is_group,
sum(is_group) over (partition by category order by ts) as groupstot


FROM
(
SELECT 
    *, 
    CASE WHEN LAG(window) OVER(PARTITION BY category ORDER BY ts  ) = window THEN 0 ELSE 1 END  is_group
FROM @TestTable 
) x

)
Select * , row_number() over(partition by category,groupstot order by ts) from ctex
ORDER BY category,ts

Gaps and Islands 根据列序查询/重置行数

Gaps and Islands query / reset row count based on column seqeunce

sql

sql-server

window-functions

gaps-and-islands