Re: analyze.c

> Hi!
>
> About analyze.c:
> If taken out vacuum, couldn't it be completly taken out of pg? Say,
> to an external program? What's the big reason not to do that? I know that
> there is some code in analyze.c (like comparing) that uses other parts of
> pg, but that seems to be easily fixed.
>
> I'm leaning toward the implementation of end-biased histograms. There is
> an introductory reference in the IEEE Data Engineering Bulletin, september
> 1995 (available on microsoft research site).

Why take it out of the backend? Seems like a real pain, especially when
you realize what functions it would have to call.

Also, keep in mind that the current analyze generates perfect estimates for
columns containing only two unique values, and columns containing only
unique values. All other cases generate imperfect statistics.

--
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