Re: hist boundary duplicates bug in head and 8.3

On Tue, 2009-01-06 at 18:40 -0500, Tom Lane wrote:
> "Nathan Boley" <npboley(at)gmail(dot)com> writes:
> >> I don't think this is a bug.
>
> > hmmm... Well, I assumed it was a bug from a comment in analyze.
>
> > From ( near ) line 2130 in analyze.c
>
> > * least 2 instances in the sample. Also, we won't suppress values
> > * that have a frequency of at least 1/K where K is the intended
> > * number of histogram bins; such values might otherwise cause us to
> > * emit duplicate histogram bin boundaries.
>
> That's talking about a case where we have a choice whether to include a
> value in the MCV list or not. Once the MCV list is maxed out, we can't
> do anything to avoid duplicates.

Surely the most important point in the OP was that ineqsel does not
correctly binary search in the presence of duplicates.

--
Simon Riggs www.2ndQuadrant.com
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