> could return at max 8999 tuples and
>
> WHERE key > 50 AND key < 70
>
> has a maximum of 998 result tuples. This would be the
> information required to make the right decision for the case
> where all rows selected are wanted.
>
> We do not have this statistical information. So the whole
> thing is at this time academic.
But we do have statistical information in pg_statistic if you run vacuum
analyze.
--
Bruce Momjian | http://www.op.net/~candle
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