Re: Selectivity of "=" (Re: [HACKERS] Index not used on simple se lect)

> FWIW, statisticians often seem worried about three values: the mean, median
> and mode. I don't really know which is which, but they are:
>
> o The average of all values
> o The average of the min and max value

We have this value. Good for > and < comparisons.

> o The most common value.

We know the number of times the most common value occurs, but not the
actual value.

>
> Someone who knows a lot more about this stuff than me can probably tell us
> how these values will affect the trust we place in the index statistics.
> Someone on this list must be able to give us some insight???
>
>
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