Re: Cross column statistics

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От Greg Stark
Тема Re: Cross column statistics
Дата
Msg-id 87u0oney8y.fsf@stark.xeocode.com
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Ответ на Re: Cross column statistics  (Christopher Kings-Lynne <chriskl@familyhealth.com.au>)
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Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes:

> > B) gather a full matrix of the level of "correlation" between each column and
> >    each other column. If this were a single floating point number per pair
> >    then it might be feasible. It would still obviously be n^2 in the number of
> >    columns though, so there would have to be some way to limit on how many
> >    columns would be analyzed this way.
> 
> Use foreign keys to just record those cross-correlations.

My email was about cross-column intra-table "correlations". inter-table
"correlations" are a whole other ball of wax.

-- 
greg



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