On 27 July 2015 at 04:58, Heikki Linnakangas <hlinnaka@iki.fi> wrote:
This patch seems sane to me, as far as it goes. However, there's no planner or executor code to use the aggregate combining for anything. I'm not a big fan of dead code, I'd really like to see something to use this.
I've attached an updated version of the patch. The main change from last time is that I've added executor support and exposed this to the planner via two new parameters in make_agg().
I've also added EXPLAIN support, this will display "Partial [Hash|Group]Aggregate" for cases where the final function won't be called and displays "Finalize [Hash|Group]Aggregate" when combining states and finalizing aggregates.
This patch is currently intended for foundation work for parallel aggregation.