From: Jaime Casanova <systemguards@gmail.com>
To: Havasvölgyi Ottó <h.otto@freemail.hu>
Cc: pgsql-sql@postgresql.org
Subject: Re: select count of distinct rows
Date: Sat, 10 Dec 2005 20:16:22 -0500
Message-ID: <c2d9e70e0512101716v396519a9s5d0ed9f4437d2d5c@mail.gmail.com> (raw)
In-Reply-To: <003001c5fded$53a2c5a0$0200a8c0@OTTO>
References: <20051209053849.498E8F0BEC@svr2.postgresql.org>
<003001c5fded$53a2c5a0$0200a8c0@OTTO>
On 12/10/05, Havasvölgyi Ottó <h.otto@freemail.hu> wrote:
> Hi,
>
> I would like to select the count of distinct rows in a table.
>
> SELECT COUNT(DISTINCT *) FROM mytable;
>
> This does not work. How can I do it with Postgres?
>
> Thanks,
> Otto
>
I guess what you need is to know how many times a single row is
duplicated so i think what you need is something like this:
SELECT fld1, COUNT(DISTINCT fld1)
FROM (SELECT ROW(*) as fld1 FROM mytable) AS foo
GROUP BY fld1;
--
regards,
Jaime Casanova
(DBA: DataBase Aniquilator ;)
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To: pgsql-sql@postgresql.org
Cc: systemguards@gmail.com, h.otto@freemail.hu
Subject: Re: select count of distinct rows
In-Reply-To: <c2d9e70e0512101716v396519a9s5d0ed9f4437d2d5c@mail.gmail.com>
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