What is the time complexity(Big O) of Cassandra operations?

Author: LotAbout

Originally Sourced from: https://stackoverflow.com/questions/39657347/what-is-the-time-complexitybig-o-of-cassandra-operations

Assume there is only one node with R rows. What is the theoretical time complexity of basic Cassandra operations?

More specifically, I want to know:

  1. key = item. I assume it to be O(log(R)) is it right?
  2. key > item, i.e. slice. Will C* fetch all R rows to judge if the condition is met, which results in O(R)? What about ordered rows?
  3. key > 10 AND key < 12. Will C* first select all that matches key > 10 and then filter with key < 12? Or C* will combine them into a single condition for query?