Tom Lane schrieb am 13.04.2016 um 15:45: >> So my question is: why is comparing a timestamp to a date so much slower? > > The date has to be up-converted to a timestamptz (not timestamp). > I think the expensive part of that is determining what timezone > applies, in particular whether DST is active. You could try it > with "localtimestamp" (no parens) instead of "now()" to see how > it performs with a non-tz timestamp. localtimestamp is indeed faster then now(), but still a bit slower then current_date (700ms vs 500ms after 5 runs for each) But as the value of now() won't change throughout the runtime of the statement (actually the transaction), I wonder why it is being converted for every row. Thomas -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general