Its the ReducerAggregate/CombinerAggregator's job to implement this logic. Look at Count and Sum that are built-in to Trident. You can also implement your own aggregator.
-Cody On Mon, Apr 21, 2014 at 2:57 PM, Raphael Hsieh <raffihs...@gmail.com> wrote: > If I am using an opaque spout and doing a persistent aggregate to a > MemcachedState, how is it aggregating/incrementing the values across all > batches ? > > I'm wanting to implement an IBackingMap so that I can use an external > datastore. However, I'm unsure where the logic goes that will read the > previous data, and aggregate it with the new data. > > From what I've been told, I need to implement the IBackingMap and the > multiput/multiget functions. So logically, I think it makes sense that I > would put this update logiv in the multiput function. However, the > OpaqueMap class already has multiGet logic in order to check the TxId of > the batch. > Instead of using an OpaqueMap class, should I just make my own > implementation ? > > Thanks > -- > Raphael Hsieh > > > > -- Cody A. Ray, LEED AP cody.a....@gmail.com 215.501.7891
