Dne 19.1.2011 20:46, Tom Lane napsal(a): > Robert Haas <robertmh...@gmail.com> writes: >> ... I guess I'm just saying I'd think really, really hard >> before abandoning the idea of periodic sampling. You have to get an >> awful lot of benefit out of those cross-column stats to make it worth >> paying a run-time cost for them. > > I've been trying to not discourage Tomas from blue-sky speculation, > but I have to say I agree with Robert that the chance of any usable > result from this approach is very very small. Feel free to do some > experimentation to prove us wrong --- but don't put a lot of effort > into it before that. > > regards, tom lane
Discourage? Not really - I have not expected this to be a simple thing to implement. And yes, it might turn out to be a dead end eventually. OTOH the approach "it seems really expensive so let's not try to build it" is a certain dead end, so I'm not going to surrender due to such speculations (althouh those are valid concerns and I'll have to address them in the future). regards Tomas -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
