Re: Surprising benchmark count(1) vs. count(*) - Mailing list pgsql-performance

On Thu, 2019-09-19 at 12:09 +0200, Thomas Kellerer wrote:
> https://blog.jooq.org/2019/09/19/whats-faster-count-or-count1/
> 
> Is there a reason why count(*) seems to be faster?

"count(*)" is just the SQL standard's way of saying what you'd
normally call "count()", that is, an aggregate without arguments.

"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.

Yours,
Laurenz Albe
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