I've thought about this for years and have never arrived on a particularly great implementation. Your idea will be maybe OK if the sets are very small and if the values don't change very often. But in a system where the values of the keys in the set change frequently (lots of tombstones) or the sets are large I think you're going to experience quite a bit of pain.
On Fri, Jan 13, 2017 at 2:14 PM Mike Torra <mto...@demandware.com> wrote: We currently use redis to store sorted sets that we increment many, many times more than we read. For example, only about 5% of these sets are ever read. We are getting to the point where redis is becoming difficult to scale (currently at >20 nodes). We've started using cassandra for other things, and now we are experimenting to see if having a similar 'sorted set' data structure is feasible in cassandra. My approach so far is: 1. Use a counter CF to store the values I want to sort by 2. Periodically read in all key/values in the counter CF and sort in the client application (~every five minutes or so) 3. Write back to a different CF with the ordered keys I care about Does this seem crazy? Is there a simpler way to do this in cassandra?
