Re: Partial Aggregation / GROUP BY before JOIN - Mailing list pgsql-hackers

On 2015/09/28 17:04, David Rowley wrote:
> On 28 September 2015 at 20:36, Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
> wrote:
> 
>>
>> Did you perhaps attach a version of the patch you didn't intend to?
>>
> 
> Oops. It seems so.
> 
> Please find the correct version attached.

Thanks, this one works fine.

By the way, you may have noticed that the append_rel_list would be broken
if the proposed optimization is applied to a appendrel parent.

CREATE TABLE sale_1() INHERITS(sale);
CREATE TABLE sale_2() INHERITS(sale);

EXPLAIN SELECT count(*) FROM sale;                     QUERY PLAN
------------------------------------------------------Finalize Aggregate  (cost=0.01..0.02 rows=1 width=0)  ->  Result
(cost=0.00..0.01rows=1 width=0)        One-Time Filter: false
 
(3 rows)

Moreover, would partial aggregation work below Append?

Thanks,
Amit