ZINTERSTORE destination numkeys key [key …] [WEIGHTS weight [weight …]] [AGGREGATE SUM|MIN|MAX]
Available since 2.0.0.
Time complexity: O(NK)+O(Mlog(M)) worst case with N being the smallest input sorted set, K being the number of input sorted sets and M being the number of elements in the resulting sorted set.
Computes the intersection of numkeys
sorted sets given by the specified keys, and stores the result in destination
. It is mandatory to provide the number of input keys (numkeys
) before passing the input keys and the other (optional) arguments.
By default, the resulting score of an element is the sum of its scores in the sorted sets where it exists. Because intersection requires an element to be a member of every given sorted set, this results in the score of every element in the resulting sorted set to be equal to the number of input sorted sets.
For a description of the WEIGHTS
and AGGREGATE
options, see ZUNIONSTORE.
If destination
already exists, it is overwritten.
*Return value
Integer reply: the number of elements in the resulting sorted set at destination
.
*Examples
redis> ZADD zset1 1 "one"
- (integer) 1
redis> ZADD zset1 2 "two"
- (integer) 1
redis> ZADD zset2 1 "one"
- (integer) 1
redis> ZADD zset2 2 "two"
- (integer) 1
redis> ZADD zset2 3 "three"
- (integer) 1
redis> ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3
- (integer) 2
redis> ZRANGE out 0 -1 WITHSCORES
- 1) "one"
- 2) "5"
- 3) "two"
- 4) "10"