"Kevin Grittner" <kevin.gritt...@wicourts.gov> writes:
> Tom Lane <t...@sss.pgh.pa.us> wrote:
>> If it should be less than 1, then what?
> 1 - (estimated tuples / estimated distinct values) ?
Uh, no. The number we're after is the probability that an outer tuple
has at least one unequal value in the inner relation. This is not 1
minus the probability that a *specific* inner value is equal, which is
what I think your formula is estimating.
regards, tom lane
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