Redis - Alternative to check existence of multiple values in a set

In my application I need have a set of values and I need to check how many of these values are present in a set in Redis.

Just to make it simple, What I want to do is something like :

> Sadd myset field1(integer) 1> Sadd myset field2(integer) 1> Sadd myset field4(integer) 1> Sismember myset field1 field4 // which is not possible as of now.

Since I can not give multiple parameters for SISMEMBER, I might have to multiple redis call which is very time consuming.

I was thinking about alternatives like pipelining but then I thought this will be a good (hacky) way of achieving it :

> Hset myhash field1 "true"(integer) 0> Hset myhash field2 "true"(integer) 0> Hset myhash field4 "true"(integer) 1> Hmget myhash field1 field2 field31) "true"2) "true"3) (nil)> Hmget myhash field1 field2 field3 field41) "true"2) "true"3) (nil)4) "true"

RedisHMGET page says the following :

Available since 2.0.0.

Time complexity: O(N) where N is the number of fields being requested.

Which is really good when compared to making multiples calls for SADD, But I am really not sure If I am 100% correct and I also don't know if there is any serious drawback of using hmget this way.

So I just wanted to the drawbacks of using hmget this way and any better approaches to solve this.