"Jim C. Nasby" <[EMAIL PROTECTED]> writes:
> On Sun, Oct 24, 2004 at 04:11:53PM -0400, Tom Lane wrote:
>> The test case you are showing is probably suffering from nonrandom
>> placement of this particular data value; which is something that the
>> statistics we keep are too crude to detect.
> Isn't that exactly what pg_stats.correlation is?

No.  A far-from-zero correlation gives you a clue that on average, *all*
the data values are placed nonrandomly ... but it doesn't really tell
you much one way or the other about a single data value.

                        regards, tom lane

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