> > The cost is "13.88" to fetch 1 row by scanning an Primary Key
> > indexed column.
> > Isn't the cost for fetching 1 row is too high ?
> I don't know, how many index pages will need to be randomly accessed
> in addition to the random heap access? How many dead versions of
> the row will need to be visited besides the row which is actually
> visible? How many of these pages are in shared_buffers? How many
> of these pages are in OS cache?
Total Index pages are 140310. Yes. I suspect most of the times the required
page is found in either OS cache or disk (shared_buffers is .9 GB) as we
have 200+ GB of highly active database and the Index is on a 10GB table.
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