Available since: 6.2.0
Time complexity: O(N)+O(M*log(M)) with N being the sum of the sizes of the input sorted sets, and M being the number of elements in the resulting sorted set.
This command is similar to
ZUNIONSTORE, but instead of storing the resulting
sorted set, it is returned to the client.
For a description of the
AGGREGATE options, see
Array reply: the result of union (optionally with their scores, in case
WITHSCORES option is given).