The simplest would be to create a stored procedure like this :
declare row as TB1%rowtype, and ret as (id integer, value numeric, subtot
numeric) then :
ret.subtot = 0
FOR row IN SELECT * FROM TB1 ORDER BY id DOret.id = row.idret.value = row.valueret.subtot = ret.subtot +
row.valueRETURNNEXT ret
END
etc...
SQL doesn't really work well for this kind of things whereas plpgsql works
really well and it's plenty fast too.
> CREATE TABLE TB1 (id integer primary key, value numeric);
> insert into tb1 values (1,20);
> insert into tb1 values (2,2);
> insert into tb1 values (3,3);
> insert into tb1 values (4,17);
> insert into tb1 values (5,-0.5);
> insert into tb1 values (6,3);
>
> I want a query that returns:
> -id- | --- value --- | --- subtot ---
> 1 | 20.00 | 20.00
> 2 | 2.00 | 22.00
> 3 | 3.00 | 25.00
> 4 | 17.00 | 42.00
> 5 | -0.50 | 41.50
> 6 | 3.00 | 44.50
>
> The subtot colum will be the "prev. subtot colum"+"value colum". :-/
> I dont know how to make the "subtot" colum, I tried to use the sum()
> function
> but it not works correctly.
> Any idea???
>
> Thanks.
>
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