Sorted set of a fixed size in Redis?

Question

I'm a rookie in using Redis, and recently have a problem when I'm thinking the solution to handle the case of high concurrency in out system, I want to use Redis, everybody know access from In-Memory is great faster than IO. Redis sorted set is the possible tool for use to do it, we want to a fixed size of sorted set to contain the user's mobile number, I Googled/Baidued a lot, didn't find any meaning message, so can anybody tell me How to specify Redis Sorted Set a fixed size? And set should tell me any add operation to sorted set is success or not?

Thanks

Answer 1

I don't think you can specify a size, that you will have to check it yourself.

You can use ZCARD

ZCARD KEY

Or you could just remove the first element ZREMRANGEBYRANK

[ZREMRANGEBYRANK][2] [KEY] 0 -[YOURSIZE]