From: Steve Crawford <scrawford@pinpointresearch.com>
To: pgsql-sql@postgresql.org
Subject: Re: why these results?
Date: Mon, 01 Aug 2011 16:01:30 -0700
Message-ID: <4E37304A.2020801@pinpointresearch.com> (raw)
In-Reply-To: <CAFjCMHuntvFO7SsGYNQrDjUwXazfnu5dgYA0BOh4eX0VcABzeA@mail.gmail.com>
References: <CAFjCMHuntvFO7SsGYNQrDjUwXazfnu5dgYA0BOh4eX0VcABzeA@mail.gmail.com>
On 08/01/2011 03:50 PM, Wes James wrote:
> select count(*) from table;
>
> count
> -------
> 100
> (1 row)
>
>
> is correct
>
> select count(*) from table where col::text ~~* '%text%';
>
> count
> -------
> 1
> (1 row)
>
> is correct.
>
> But now if I do:
>
>
> select count(*) from table where col::text !~~* '%text%';
> count
> -------
> 98
> (1 row)
>
> Shouldn't it be 99? That is out of 100 records there is one that has
> "text" in column "col" so the !~~* should return 99 rows. ??
>
> -wes
>
select count(*) from table where col is null;
(null is neither equal nor not-equal to anything, even null)
Cheers,
Steve
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Subject: Re: why these results?
In-Reply-To: <4E37304A.2020801@pinpointresearch.com>
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