Re: Partition-wise aggregation/grouping

On Thu, Sep 21, 2017 at 5:00 PM, Rajkumar Raghuwanshi <
rajkumar(dot)raghuwanshi(at)enterprisedb(dot)com> wrote:

> Hi Jeevan,
>
> while testing latest v3 patches, I am getting a server crash if I reset
> partition_wise_agg_cost_factor, please take a look.
>
> CREATE TABLE lp (a TEXT, b FLOAT, c INT) PARTITION BY LIST(c);
> CREATE TABLE lp1 PARTITION OF lp FOR VALUES IN (10,20);
> CREATE TABLE lp2 PARTITION OF lp FOR VALUES IN (30,40);
>
> INSERT INTO lp VALUES ('a1',800, 20);
> INSERT INTO lp VALUES ('a2',1250,30);
> INSERT INTO lp VALUES ('a3',2975,20);
> INSERT INTO lp VALUES ('a3',2850,30);
>
> postgres=# SET enable_partition_wise_agg TO true;
> SET
> postgres=# SET partition_wise_agg_cost_factor TO 0.5;
> SET
> postgres=#
> postgres=# SELECT MAX(b), AVG(b) FROM lp GROUP BY a HAVING a = 'a3' ORDER
> BY 1,2;
> max | avg
> ------+--------
> 2975 | 2912.5
> (1 row)
>
> postgres=# RESET partition_wise_agg_cost_factor;
> RESET
> postgres=#
> postgres=# SELECT MAX(b), AVG(b) FROM lp GROUP BY a HAVING a = 'a3' ORDER
> BY 1,2;
> 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.
> !>
>
>
Oops. Will fix this.

I have added these tests in testcase, but testcase is working as expected.
However running those steps on psql reproduces the crash (not consistent
though).

Looking into it. Thanks for reporting.

> Thanks & Regards,
> Rajkumar Raghuwanshi
> QMG, EnterpriseDB Corporation
>

--
Jeevan Chalke
Principal Software Engineer, Product Development
EnterpriseDB Corporation
The Enterprise PostgreSQL Company