sinterstore

sinterstore(intersection store) 将两个集合的交集，保存到新的集合中，返回的是交集元素个数

127.0.0.1:6379> smembers set1
1) "1"
2) "2"
3) "3"
127.0.0.1:6379> smembers set2
1) "1"
2) "2"
3) "3"
4) "4"
127.0.0.1:6379> sinterstore destination set1 set2
(integer) 3 交集集合中的元素有3个
127.0.0.1:6379> smembers destination
1) "1"
2) "2"
3) "3"
----------------------------------------------------
127.0.0.1:6379> smembers set3
1) "1"
2) "2"
3) "3"
127.0.0.1:6379> smembers set4
1) "4"
2) "5"
3) "6"
127.0.0.1:6379> sinterstore destination set3 set4
(integer) 0 交集集合中的元素为0个
127.0.0.1:6379> smembers destination
(empty list or set)