>
> I want to create a sequence that increases in unit column 3 for each
> record individually in column 2
>
> How do i create a sequence that can manage this?
> Is there a solution for this?
>
Yeah, depesz shows how to do this here
http://www.depesz.com/index.php/2007/08/17/rownum-anyone-cumulative-sum-in-one-query/