questions about CLUSTER

After reviewing http://www.postgresql.org/docs/8.3/static/sql-cluster.html a
couple of times, I have some questions:
1) it says to run analyze after doing a cluster. i'm assuming autovacuum will
take care of this? or should i go ahead and do the analyze 'now' instead of
waiting?
2) is there any internal data in the db that would allow me to
programmatically determine which tables would benefit from being clustered?
3) for that matter, is there info to allow me to determine which index it
should be clustered on in cases where the table has more than one index?
4) for tables with >1 indexes, does clustering on one index negatively impact
queries that use the other indexes?
5) is it better to cluster on a compound index (index on lastnamefirstname) or
on the underlying index (index on lastname)?

tia
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Douglas J Hunley (doug at hunley.homeip.net) - Linux User #174778
http://doug.hunley.homeip.net

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