On 2013-10-01 10:07:19 -0400, Robert Haas wrote: > - It seems that HeapSatisfiesHOTandKeyUpdate is now > HeapSatisfiesHOTandKeyandCandidateKeyUpdate. Considering I think this > was merely HeapSatisfiesHOTUpdate a year ago, it's hard not to be > afraid that something unscalable is happening to this function. On a > related node, any overhead added here costs broadly; I'm not sure if > there's enough to worry about.
Ok, I had to think a bit, but now I remember why I think these changes are not really problem: Neither the addition of keys nor candidate keys will add any additional comparisons since the columns compared for candidate keys are a subset of the set of key columns which in turn are a subset of the columns checked for HOT. Right? Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
