Re: BUG #8410: out of binary heap slots

On 2013-08-30 23:05:25 +0200, Andres Freund wrote:
> On 2013-08-30 23:00:15 +0200, Andres Freund wrote:
> > Hi,
> >
> >
> > On 2013-08-30 20:46:27 +0000, terje(at)elde(dot)net wrote:
> > > I'm getting "out of binary heap slots", which offcourse spoils the fun of
> > > the query.
> >
> > > Explain analyze gives this plan (again anonymized a bit, but can send proper
> > > off-list):
> >
> > Since I reviewed the patch that introduced that message, I'd be
> > interested in getting that. Ideally in a state where I can reproduce the
> > issue in a new cluster.
>
> No need, found the bug. And I think can build a testcase myself.
>
> ExecReScanMergeAppend resets ms_initialized, but doesn't clear the
> binaryheap. Thus no new elements fit.

Ok, patch for that attached. Should we add
SELECT (SELECT g.i FROM ((SELECT random()::int ORDER BY 1 OFFSET 0) UNION ALL (SELECT random()::int ORDER BY 1 OFFSET 0)) f(i) ORDER BY f.i LIMIT 1) FROM generate_series(1, 10) g(i);
as a regression test? I slightly on the "no" side...

Greetings,

Andres Freund

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