Hi flybyGWT,

Actually my example involved a client cache handled on GWT side.
The "updateMyInternalCahce" method updates such a cahce for every changed field and the "onItemUpdate" informs the GWT side about which row needs the update.
But I think that, in practice, it is not very different from your solution.

As regards the management of the super data set and subs data sets, I confirm you that both solutions are fully supported by Lightstreamer. Choose which one is the best depends on the use cases of your application.
For example if if all the data of the super set are displayed simultaneously or only a small portion and in this second case, the frequency of changes from a subs set into another.

By the way, I know that it is not GWT but, please refer to this demo for an example of dynamic subsets subscription.