Re: Use "average field correlation per hard disk

At 04:08 PM 10/03/2004, Tom Lane wrote:
>None at the moment, but I'm open to suggestions. It seems like we might
>need different stats for equality probes than range probes.

What about my suggestion from August 2000:

"There might be a way to side-step the issue here. I assume that
the index nodes contain a pointer to a record in a file, which
has some kind of file position. By comparing the file positions
on one leaf node, and then averaging the node cluster values,
you might be able to get a pretty good idea of the *real* clustering."

I don't use the CLUSTER command, but I have clustered data and would like
to be able to take advantage of the fact if possible. *If* the record
pointers can be used to indicate closeness, then the same approach of
randomly sampling index nodes would seem to work. Then again, maybe I don't
know enough about the storage techniques...

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