scard

scard(set cardinality [kɑːdɪ'nælɪtɪ] 基数) 返回集合中的元素总数

127.0.0.1:6379> smembers testSet
1) "1"
2) "2"
3) "3"
4) "4"
5) "5"
6) "6"
7) "7"
8) "8"
9) "9"
127.0.0.1:6379> scard testSet
(integer) 9