Thomas Kellerer <spam_eater@xxxxxxx> writes: > Laurenz Albe schrieb am 19.09.2019 um 12:22: >> "count(1)" has to check if 1 IS NULL for each row, because NULL >> values are not counted. "count(*)" doesn't have to do that. > But 1 is a constant, why does it need to check it for each row? [ shrug... ] There's no special optimization for that case. And I can't say that it seems attractive to add one. regards, tom lane
