Scott Marlowe wrote:
> On Tue, 2006-03-07 at 11:15, Alvaro Herrera wrote:
> > Scott Marlowe wrote:
> > 
> > > Lastly, I noticed that after you clusters on all your indexes, the query
> > > planner switched from a merge join to a hash join, and it was slower. 
> > > You might wanna try turning off hash joins for a quick test to see if
> > > merge joins are any faster.
> > 
> > Anyway please note that clustering "all indexes" does not really make
> > sense.  You can cluster only on one index.  If you cluster on another,
> > then the first clustering will be lost.  Better make sure to cluster on
> > the one index where it makes the most difference.
> 
> Note that I was referring to his clustering on an index for each table. 
> I.e. not on every single index.  but he clustered on four tables /
> indexes at once, so that was what I was referring to.  Sorry for any
> confusion there.

Ah, sorry, I misinterpreted.

> So, do you see any obvious, low hanging fruit here?

Sorry, I didn't look at his test case very closely :-(

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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