On Tue, Mar 10, 2020 at 9:12 PM Andy Fan <zhihui.fan1...@gmail.com> wrote: > > > Hi Tom & David & Bapat: > > Thanks for your review so far. I want to summarize the current issues to help > our following discussion. > > 1. Shall we bypass the AggNode as well with the same logic. > > I think yes, since the rules to bypass a AggNode and UniqueNode is exactly > same. > The difficulty of bypassing AggNode is the current aggregation function call > is closely > coupled with AggNode. In the past few days, I have make the aggregation call > can > run without AggNode (at least I tested sum(without finalized fn), avg (with > finalized fn)). > But there are a few things to do, like acl check, anynull check and maybe > more check. > also there are some MemoryContext mess up need to fix. > I still need some time for this goal, so I think the complex of it deserves > another thread > to discuss it, any thought?
I think if the relation underlying an Agg node is know to be unique for given groupByClause, we could safely use AGG_SORTED strategy. Though the input is not ordered, it's sorted thus for every row Agg node will combine/finalize the aggregate result. -- Best Wishes, Ashutosh Bapat
