Hello, At Fri, 6 Nov 2015 09:49:30 +0530, Amit Kapila <amit.kapil...@gmail.com> wrote in <caa4ek1l_5t-uysqemorx54g3qexghhak5yfmzzqu5midzxz...@mail.gmail.com> > Apart from other problems discussed, I think it could also lead to > a performance penality for the cases when the qual condition is > costly as evaluating such a qual against lot of dead rows would be a > time consuming operation. I am not sure, but I think some of the > other well know databases might not have any such problems as > they store visibility info inside index due to which they don't need to > fetch the heap tuple for evaluating such quals.
I was junst thinking of the same thing. Can we estimate the degree of the expected penalty using heap statistics? Of couse not so accurate though. regards, -- Kyotaro Horiguchi NTT Open Source Software Center -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
