ZUNION
Syntax
ZUNION numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE <SUM | MIN | MAX>] [WITHSCORES]
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 WEIGHTS and AGGREGATE options, see ZUNIONSTORE.
Return
Array reply: the result of union (optionally with their scores, in case
the WITHSCORES option is given).
Examples
dragonfly> ZADD zset1 1 "one"
(integer) 1
dragonfly> ZADD zset1 2 "two"
(integer) 1
dragonfly> ZADD zset2 1 "one"
(integer) 1
dragonfly> ZADD zset2 2 "two"
(integer) 1
dragonfly> ZADD zset2 3 "three"
(integer) 1
dragonfly> ZUNION 2 zset1 zset2
1) "one"
2) "three"
3) "two"
dragonfly> ZUNION 2 zset1 zset2 WITHSCORES
1) "one"
2) "2"
3) "three"
4) "3"
5) "two"
6) "4"