"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 ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend