On Mon, Jan 28, 2013 at 6:03 PM, Jacques Nadeau <[email protected]>wrote:
> ... > How do people feel about CollapseAggregate and RunningAggregate. I'm > inclined to stay away from the GroupBy name since a traditional SQL group > by is really Group followed by CollapseAggregate. I've also been > considering using the MS SQL Server naming of "Segment" instead of "Group". > Anyone have any opinions on that? > Segment has worked for me as I was reading the syntax document. It has an intuitive meaning and little semantic collision with other concepts. > > OK. We need a new name. Nominations are open. > > > > CollapseAggregate is my vote. > Fine by me. > > > > And there is a third kind which is the running aggregate, but those are > > plausibly an windowed aggregate with infinite extent backwards. > > > > One option of the windowing operator is a full backward window. > Yes. The running aggregate can handle all of these cases. > > You raise an interesting point here. The current argument structure is > > deficient. We currently have before and after. I think that should be > > restated to start and end indexes with negative indexes to indicate > > preceding records. Your point here implies that we should also have a > > starting expression and an ending expression. > > I'm not sure we're deficient. The before and after are based within the > segment key. > I really think that we are deficient. There is a much simpler representation that I outlined in my comments to the syntax document. Basically, all of the kinds of windows that are based on indexes can easily be handled with one structure that is based on index limits. Much simpler than what is currently specified. > > Should I take a stab at a revised specification for aggregation? I > dislike > > the groupBy name for an aggregation, but could be convinced by a show of > > hands. > > > > I can take a shot at this. > Great.
