Horton

Re: COUNT(*) again (was Re: [HACKERS] Index/Function organized

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Hannu Krosing <hannu@tm.ee>, Christopher Browne <cbbrowne@libertyrms.info>, pgsql-performance@postgresql.org, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2003-10-05T04:20:32Z
Lists: pgsql-hackers, pgsql-performance 
Tom Lane wrote:
> Hannu Krosing <hannu@tm.ee> writes:
> > The point I was trying to make was that faster count(*)'s is just a side
> > effect. If we could (conditionally) keep visibility info in indexes,
> 
> I think that's not happening, conditionally or otherwise.  The atomicity
> problems alone are sufficient reason why not, even before you look at
> the performance issues.

What are the atomicity problems of adding a create/expire xid to the
index tuples?

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