A jira created: https://issues.apache.org/jira/browse/APEXMALHAR-2428
On Mon, Feb 27, 2017 at 9:53 AM, Bright Chen <bri...@datatorrent.com> wrote: > I think Chimay's proposal could make application more clear and increase > the performance as locate of key/window cost most of time. > > A suggested usage for Composite Accumulation could as following: > > * //following is the sample code how to add sub accumulations* > > * CompositeAccumulation<Long> accumulations = new > CompositeAccumulation<>();* > > * AccumulationTag sumTag = > accumulations.addAccumulation((Accumulation)new SumAccumulation());* > > * AccumulationTag countTag = > accumulations.addAccumulation((Accumulation)new Count());* > > * AccumulationTag maxTag = accumulations.addAccumulation(new Max());* > > * AccumulationTag minTag = accumulations.addAccumulation(new Min());* > > * //following is the sample how to get the sub-accumulation output* > > * accumulations.getSubOutput(sumTag, outputValues)* > > * accumulations.getSubOutput(countTag, outputValues)* > > * accumulations.getSubOutput(maxTag, outputValues)* > > * accumulations.getSubOutput(minTag, outputValues)* > > > Thanks > > Bright > > On Sun, Feb 26, 2017 at 10:33 PM, Chinmay Kolhatkar < > chin...@datatorrent.com> wrote: > >> Dear Community, >> >> Currently we have accumulations for individual types of accumulations. >> But if one wants to do more than one accumulations in a single stage of >> Windowed Operator it is not possible. >> >> I want to propose an idea about "CompositeAccumulation" where more than >> one >> accumulation can be configured and this accoumulation can relay on >> multiple >> accumulations to generate final result/output. >> >> The output can be either of the 2 forms: >> 1. Just the list of outputs with AccumulationTags as identifiers. >> 2. Merge the results of multiple accumulations using some user defined >> logic. >> For eg. In aggregation case, Input POJO to this accumulation can be a >> POJO containing NumberOfOrders as field and in output one might need to >> generate a final(single) POJO which contains result of multiple >> accumulations like SUM, COUNT on NumberOfOrders as different fields of >> outgoing POJO. >> >> I particularly see the use of this for Multiple Aggregation which we would >> like to do in SQL on Apex Integration. >> >> Please share your thoughts on the same. >> >> Thanks, >> Chinmay. >> > >
