Re: Re: Poor cost estimate with interaction between table correlation and partial indexes

On Sun, Aug 27, 2017 at 8:31 PM, Michael Malis <michaelmalis2(at)gmail(dot)com> wrote:
> (Sorry David. I initially replied only to you)
>
> Ok. I've attached a patch of a proof-of-concept. I have a few
> questions about tests.
>
> What is typical workflow to add tests for changes to the planner?

Add submitted patches at commitfest.postgresql.org

> Also
> I ran make check and it appears one of the existing tests is failing.
> What is a typical way for going about discovering why the query plan
> for a specific query changed?

I don't have any magic answer on this point.

> Also, how should I go about changing the
> old test? Should I replace the old test output with the new test
> output or modify the old test slightly to get it to produce the same
> case as before?

That's a judgement call, based on what you think the point of the test was.

--
Robert Haas
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