用 windows 函数减去两列

Question

如何减去两列：

我有 table:

      ID      COL 1      COL 2
     -------------------------
       1      200.00     70.00
       2      200.00     30.00
       3      200.00     90.00
       4      200.00    110.00

Col1 - COL2 但要继续每一行，并且值会减少之前的值

我的输出如下：

      ID      COL 1      COL 2     [COL3 AS RESULT]
     -------------------------
       1      200.00     70.00          130 
       2      200.00     30.00          100
       3      200.00     90.00           10
       4      200.00    110.00         -100

Answer 1

看来你想从col1中减去col2的累计量：

select id, col1, col2,
       (col1 - sum(col2) over (order by id)) as col3
from t;

Answer 2

您需要递归 CTE 才能获得运行总数 -

with cte as
(
select id,col1,col2,cast(col1 - col2 as decimal(5,2)) as val
from #a
where id = 1
union all
select b.id,b.col1,b.col2,cast(a.val - b.col2 as decimal(5,2))
from cte as a
inner join #a as b
on b.id = a.id + 1
)select * from cte

用 windows 函数减去两列

Subtract two columns with windows function

sql

tsql

sql-server

sql-server-2014