You can't create nested structures in Redis, 
meaning you can't (for example) store a native redis list inside a native redis hash-map.

aerospike 更强大   
支持复杂嵌套数结构 支持多线程 良好的集群支持


If you really need nested structures, 
you might want to just store a JSON-blob (or something similar) instead. 
Another option is to store an "id"/key to a different redis object as the value of the map key, 
but that requires multiple calls to the server to get the full object.

redis只支持Hashmap< String,String >


使用 json 
拆分成多个 key   avg = sum /count   分别存 sum 和 count

Object-hash mapping library for Redis.
https://github.com/soveran/ohm