Sorry for top-posting -- challenged reader.

Can't speak directly to PostgreSQL but in Informix the fill factor is useful 
for tweaking indexes. A very high fill factor is useful for tables that are 
static -- any inserts or changes to the index trigger a *lot* of moving of 
b-tree branches. But the high fill factor means that each page has more useful 
data references in it. A very low fill factor means that pages are "sparse" and 
so inserts and updates are less likely to trigger massive b-tree rebalancings. 

I've never used it on PostgreSQL (yet!) but am looking forward to it.

Beware of premature optimization!

HTH,

Greg Williamson
Senior DBA
GlobeXplorer LLC, a DigitalGlobe company

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-----Original Message-----
From: [EMAIL PROTECTED] on behalf of Richard Broersma Jr
Sent: Tue 9/18/2007 10:29 AM
To: Phoenix Kiula; Bill Moran
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] For index bloat: VACUUM ANALYZE vs REINDEX/CLUSTER
 
--- Phoenix Kiula <[EMAIL PROTECTED]> wrote:

> What constitutes a "small fill factor"? Would 70 be good? I guess my
> current must have been the default, which the manual says is 100.

On the following link:

http://www.postgresql.org/docs/8.2/interactive/sql-createindex.html#SQL-CREATEINDEX-STORAGE-PARAMETERS

I found this:

"B-trees use a default fillfactor of 90, but any value from 10 to 100 can be 
selected."

Regards,
Richard Broersma Jr.

---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
       choose an index scan if your joining column's datatypes do not
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