Re: Surprising benchmark count(1) vs. count(*)

Tom Lane <[email protected]>
Newsgroups gmane.comp.db.postgresql.performance
Message-ID <[email protected]> 
Thomas Kellerer <[email protected]> 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
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