I use Memcached to store content lists with very key combinations, when user edited the content, I must refresh the cache, but it is hard to say what particular list to refresh, it is not either a good idea to flush the entire Memcached server, so my question is: Can I group the Memcached keys so that I can flush a group but the total Memcached?
Memcached does not have support for range queries so unfortunately you cannot flush a subset of keys.