On 21 Oct 2010, at 24:28, Raymond O'Donnell wrote: >> and i'd like to be able to wite a query that would result in >> >> 1,A,B >> 2,A,C >> 3,A,D >> [...] >> >> PG version is 8.3. >> >> Any ideas? > > You probably want generate_series(): > > http://www.postgresql.org/docs/8.3/static/functions-srf.html
I'm currently using WebFOCUS at work and they have a LAST operator, referring to the value a column had in the last returned row. That's pretty good for stuff like this, so I wonder if it wouldn't be beneficial to have something like that in Postgres? SQL isn't FOCUS, but in SQL it would work something like this: SELECT COALESCE(LAST foo +1, 1) AS foo, bar FROM table; foo | bar ----+----- 1 | Apple 2 | Banana 3 | Orange 4 | Lemon Or for fun, SELECT COALESCE(LAST foo *2, 1) AS foo, bar || COALESCE(LAST bar, '') AS bar FROM table; foo | bar ----+------------------------ 1 | Apple 2 | BananaApple 4 | OrangeBananaApple 8 | LemonOrangeBananaApple Of course being able to use LAST requires that there's still a copy of the last returned row lingering in a buffer somewhere. If we have that, great! If we don't, well, it depends on how much the devs desire such a feature :) Alban Hertroys -- Screwing up is an excellent way to attach something to the ceiling. !DSPAM:737,4cc0277010283330040792! -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
