> a create index updates the statistics in pg_class,
> this leads to substantial performance degradation compared to
> 6.4.2.
> 
> If you want to see what I mean simply run the performance test in
> our test subdirectory.
> 
> I think the create index statement should not update this statistic.
> (at least not in the newly created empty table case) 
> This behavior would then be in sync with the create table behavior.
> 
To fix this I urgently suggest the following patch:
 <<index.patch>> 
regression passes and is a little faster :-)
performance test: without patch 7min now 22 sec

Andreas
Tue, 25 May 1999 20:05:50 +0200
ZEUGSWETTER Andreas IZ5 <Andreas.Zeugswetter@telecom.at>
Re: create index updates nrows statistics
I had this patch, but was unsure if it was save for 6.5.

Looks like Tom has decided.  Good.


> > a create index updates the statistics in pg_class,
> > this leads to substantial performance degradation compared to
> > 6.4.2.
> > 
> > If you want to see what I mean simply run the performance test in
> > our test subdirectory.
> > 
> > I think the create index statement should not update this statistic.
> > (at least not in the newly created empty table case) 
> > This behavior would then be in sync with the create table behavior.
> > 
> To fix this I urgently suggest the following patch:
>  <<index.patch>> 
> regression passes and is a little faster :-)
> performance test: without patch 7min now 22 sec
> 
> Andreas

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Wed, 26 May 1999 20:10:29 -0400 (EDT)
Bruce Momjian <maillist@candle.pha.pa.us>
Re: [HACKERS] Re: create index updates nrows statistics