Hello, I'd like to get some ideas on how to model counting uniques with cassandra. My use-case is that I have various counters that I increment based on data received from multiple devices. I'd like to be able to know if at least X unique devices contributed to a counter value. I've thought of the idea of building a key per counter and then using columns whose name would be the device ids but it might grow very very large and I don't see how to prune it effeciently. Any ideas ?
Thanks
