Re: sequential scan on select distinct - Mailing list pgsql-performance

From Tom Lane
Subject Re: sequential scan on select distinct
Date
Msg-id 199.1097170001@sss.pgh.pa.us
Whole thread Raw
In response to Re: sequential scan on select distinct  (Ole Langbehn <ole@freiheit.com>)
Responses Re: sequential scan on select distinct  (Pierre-Frédéric Caillaud<lists@boutiquenumerique.com>)
Re: sequential scan on select distinct  (Mischa Sandberg <ischamay.andbergsay@activestateway.com>)
List pgsql-performance
Ole Langbehn <ole@freiheit.com> writes:
>> What do you think about the idea of an "UniqueSort" which would do
>> sort+unique in one pass ?

> This is what oracle does and it is quite fast with it...

Hashing is at least as fast, if not faster.

            regards, tom lane

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