> > 1) You have n^2 possible two-column combinations. That's a lot of
> > processing and storage.
> Yes, that's the hard problem to solve. Actually, btw, it's n!, not n^2.
Ooops, bad math. Andrew pointed out it's actually n*(n-1)/2, not n!.
Also, we could omit columns unlikely to correlate, such as large text
columns, bytea and numerics with high precisions. Also, we probably don't
need to correlate UNIQUE columns inside ... I think.
PostgreSQL @ Sun
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