Re: (P)SQL for a sum with constraints

In response to Shug Boabby :
> Hello all,
>
> I have a table with 2 bigint columns, let's call them A and B. I need
> a query that will allow me to return A alongside the sum of Bs from
> rows where A is less than or equal to this row's A. It is best
> described with some example data, consider the following:
>
> A B
> 1 0
> 2 1
> 3 0
> 4 2
> 5 1
>
> I want to be able to make a query that returns the following rows:
>
> A funkySumB
> 1 0
> 2 1
> 3 1
> 4 3
> 5 4
>

wait for 8.4:

test=# select * from shug ;
a | b
---+---
1 | 0
2 | 1
3 | 0
4 | 2
5 | 1
(5 rows)

test=# select a, sum(b) over (order by a) from shug ;
a | sum
---+-----
1 | 0
2 | 1
3 | 1
4 | 3
5 | 4
(5 rows)

Andreas
--
Andreas Kretschmer
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