It sounds like you want a persistentAggregate to occur before the stream grouping by word, would this work? in pseudo trident DSL:
Stream words = ...; words.groupBy(word).persistentAggregate(...); words.persistentAggregate(...); On Tue, Jun 24, 2014 at 12:45 PM, Can Gencer <cgen...@gmail.com> wrote: > Hi all, > > I'm wondering what is the best way to "chain" persistent aggregations in > Trident. > > Let's say I have a running count of words and I also want to do another > aggregation to calculate the total count of all words using the results of > the previous aggregation. > > I can use a persistentAggregate to calculate the running total for each > word. However I can't use another persistentAggregate directly chained to > that as that would only add the new value instead of decrementing the old > value for the group first. > > What is the best solution to this scenario? Does storm have a way to > handle this out of the box? > > Regards, > Can >