On Apr 10, 2012, at 1:52, <mika(at)digikartta(dot)net> wrote:
>
> Quite challanging, right?
>
Aside from the possibly extremely rare case where this is actually functional the only challenging task is to tell off whomever gave you the idea/requirement that your schema is desirable - even if that person is yourself.
That aside, judicious use of CASE constructs, and probably UNION, will get you your answers. Keep in mind that you likely need to end up casting all of your values to varchar/text in the end.
You may also want to look at the HSTORE extension.
Given the generic nature of your inquiry actual specific advice is impossible to give.
David J.