Re: clustering by partial indexes - Mailing list pgsql-general

From Bruce Momjian
Subject Re: clustering by partial indexes
Date
Msg-id 200511151808.jAFI8ov12643@candle.pha.pa.us
Whole thread Raw
In response to Re: clustering by partial indexes  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: clustering by partial indexes  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Tom Lane wrote:
> "Keith C. Perry" <netadmin@vcsn.com> writes:
> > Quoting Tom Lane <tgl@sss.pgh.pa.us>:
> >> "Keith C. Perry" <netadmin@vcsn.com> writes:
> >>> This might have been discussed before but I wanted to know if clustering
> >>> tables by partial indexes will be availble in a later release of pgSQL?
> >>
> >> What in the world would it mean to do that?
>
> > I'm not sure I understand your question.
>
> CLUSTER says "order the table according to the order of the entries in
> this index".  A partial index doesn't define an ordering for the whole
> table, only the rows that have entries in that index.  So it doesn't
> seem to me that you are asking for something that has a well defined
> meaning.

I assume it would cluster the part of the table covered by the partial
index, and the rest of the table would be in any order.  It seems like
reasonable behavior, though this is the first request I can remember.

--
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