On Mon, Jun 5, 2017 at 8:22 AM, atorikoshi
<torikoshi_atsushi_z2@lab.ntt.co.jp> wrote:
> Hi,
>
> I found below formula to compute selectivities, but
> I think the last Probability 'P(b=?)' should be 'P(c=?)'.
>
>> P(a=?,b=?,c=?) = P(a=?,b=?) * (d + (1-d)*P(b=?))
>
>
> Attached patch fixes it, and it also adds some spaces
> following another formula which is on line 86 and
> computes P(a=?, b=?).
Agree. Also using "d" for "degree of functional dependence (b=>c) as
well is confusing. We are already using "d" for "degree of functional
dependence (a=>b). Here' patch to use "d'" instead of "d".
--
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company
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