Re: Server crashed with dense_rank on partition table.

On 13 June 2018 at 17:55, Michael Paquier <michael(at)paquier(dot)xyz> wrote:
> On Wed, Jun 13, 2018 at 11:08:38AM +0530, Rajkumar Raghuwanshi wrote:
>> postgres=# SELECT dense_rank(b) WITHIN GROUP (ORDER BY a) FROM pagg_tab
>> GROUP BY b ORDER BY 1;
>> server closed the connection unexpectedly
>> This probably means the server terminated abnormally
>> before or while processing the request.
>> The connection to the server was lost. Attempting reset: Failed.
>
> Indeed, thanks for the test case. This used to work in v10 but this is
> failing with v11 so I am adding an open item. The plans of the pre-10
> query and the query on HEAD are rather similar, and the memory context
> at execution time looks messed up.

Looks like some memory is being stomped on somewhere.

4b9094eb6 (Adapt to LLVM 7+ Orc API changes.) appears to be the first
bad commit.

--
David Rowley http://www.2ndQuadrant.com/
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