this is the simple demo which is based on the extension of phpredis and the nosql db of redis

1. this demo depend on the phpredis and redis.you will have to be used
2. the redis's structure is following
   • hashmap(store the login username and password)
     • key:login
     • member:user1 or user2 or usern
     • value:password
   • sorted sets(create n keys when we have n users)
     • key:user2-content(or user1-content)
     • score:timestamp(the content createtime)
     • value:content
   • string(create n keys when we have n users)
     • key:user2-timestamp
     • value:timestamp(the user last content's timestamp)

the string timestamp is the best key;