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Re: Oddball data distribution giving me planner headaches

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--- On Fri, 12/2/11, Tom Lane <tgl@xxxxxxxxxxxxx> wrote:

> The only real fix for that will require cross-column
> statistics, which
> we don't have yet --- without such, there's no way for the
> planner to
> know that distributors have an atypical number of child
> customers.


The only caveat that I can think of here is that each of the customer_id's in the subselect ARE in the MCV list for the parent_customer column for that customer_rel table.  If I had listed SPECIFIC customer ids in the subselect, I would get spot-on row estimates.  Is there anything there that gives me any hope?




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