title: How to efficiently union non-overlapping sets in redis?
body: <p>I have a use case where I know for a fact that some sets I have materialized in my redis store are disjoint. Some of my sets are quite large, as a result, their <code>sunion</code> or <code>sunionstore</code> takes quite a large amount of time. Does redis provide any functionality for handling such unions?</p>
  
  <p>Alternatively, if there is a way to add elements to a set in Redis without checking for uniqueness before each insert, it could solve my issue.</p>