SINTERSTORE destination key [key ...]
Available since: 1.0.0
Time complexity: O(N*M) worst case where N is the cardinality of the smallest set and M is the number of sets.
ACL categories:
@write
@set
@slow
This command is equal to SINTER, but instead of returning the resulting set,
it is stored in destination.
If destination already exists, it is overwritten.
Return
Integer reply: the number of elements in the resulting set.