Re: Aggregate Push Down - Performing aggregation on foreign server

On Thu, Sep 8, 2016 at 10:41 PM, Ashutosh Bapat <
ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:

>
>
>
>
>> While checking for shippability, we build the target list which is passed
>> to
>> the foreign server as fdw_scan_tlist. The target list contains
>> a. All the GROUP BY expressions
>> b. Shippable entries from the target list of upper relation
>> c. Var and Aggref nodes from non-shippable entries from the target list of
>> upper relation
>>
>
> The code in the patch doesn't seem to add Var nodes explicitly. It assumes
> that
> the Var nodes will be part of GROUP BY clause. The code is correct, I
> think.
>

Yes. Code is correct. Var nodes are already part of GROUP BY else we hit
error well before this point.

Thanks Ashutosh for the detailed review comments.

I am working on it and will post updated patch once I fix all your concerns.

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