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Re: count(*) vs count(id) - Mailing list pgsql-general

From	Matt Zagrabelny
Subject	Re: count(*) vs count(id)
Date	February 2, 2021 05:31:31
Msg-id	CAOLfK3UqHe1urYNhmoT0wp=fx3mniNHaTqjmzJoiFu4jqBQOBw@mail.gmail.com Whole thread Raw
In response to	Re: count(*) vs count(id) (Guillaume Lelarge <guillaume@lelarge.info>)
List	pgsql-general

On Mon, Feb 1, 2021 at 7:19 PM Guillaume Lelarge <guillaume@lelarge.info> wrote:

You're doing a left join, so I guess there's no row where call_records.timestamp::date = 2020-08-30. That would result with a NULL id.

Thanks for the excellent analysis everyone. I appreciate it!

Here is the documentation (for anyone reading the mailing list in the future...)

`count(*)`		`bigint`	number of input rows
`count(expression)`	any	`bigint`	number of input rows for which the value of `expression` is not null

Have a great night (or equivalent for your TZ).

-m

From: rob stone
Date: 02 February 2021, 04:52:05
Subject: Re: libpq and mysterious "invalid byte sequence for encoding UTF8".

From: Tom Lane
Date: 02 February 2021, 05:53:45
Subject: Re: libpq and mysterious "invalid byte sequence for encoding UTF8".