Re: Formulating an sql query with CTID - Mailing list pgsql-hackers

From Martijn van Oosterhout
Subject Re: Formulating an sql query with CTID
Date
Msg-id 20060729162539.GA4599@svana.org
Whole thread Raw
In response to Formulating an sql query with CTID  (Tzahi Fadida <Tzahi.ML@gmail.com>)
Responses Re: Formulating an sql query with CTID  (Hannu Krosing <hannu@skype.net>)
List pgsql-hackers
On Sat, Jul 29, 2006 at 03:37:15AM +0300, Tzahi Fadida wrote:
> Hi,
> I have a query i am having trouble to formulate:
> I used to do:
> SELECT DISTINCT a0,a1 FROM public.t1
> However, now i need to add the CTID attribute, but CTID is unique
> thus, distinct is useless. In addition, i can't seem to be able to use max()
> etc... or casting to anything on CTID in order to use group by technique.

Use DISTINCT ON, see the docs for details.

http://www.postgresql.org/docs/7.4/static/queries-select-lists.html

That's for an older version, but it still works the same, google isn't
delivering the newer version...

Have an nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.

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