使用 T-SQL 中一行的先前值计算值 [英] Calculating value using previous value of a row in T-SQL

问题描述

我得到了下表，想在不使用游标或 while 循环的情况下，使用 sql 中前一行的同一列 (Column2) 的值来计算每行 Column2 的值.

I got following table and want to calculate value of Column2 on each row using the value of the same column (Column2) from the previous row in a sql without using cursor or while loop.

Id   Date             Column1    Column2
1    01/01/2011       5          5 => Same as Column1
2    02/01/2011       2          18 => (1 + (value of Column2 from the previous row)) * (1 + (Value of Column1 from the current row)) i.e. (1+5)*(1+2)
3    03/01/2011       3          76 => (1+18)*(1+3) = 19*4
and so on

有什么想法吗?

推荐答案

假设 递归 CTE:

;with cteCalculation as (
    select t.Id, t.Date, t.Column1, t.Column1 as Column2
        from YourTable t
        where t.Id = 1
    union all
    select t.Id, t.Date, t.Column1, (1+t.Column1)*(1+c.Column2) as Column2
        from YourTable t
            inner join cteCalculation c
                on t.Id-1 = c.id
)
select c.Id, c.Date, c.Column1, c.Column2
    from cteCalculation c

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