The innodb_memcache daemon plugin is a plugin for the MySQL Server end contains an embedded memcached. This embedded memcached is configured to use MySQL's InnoDB engine as storage backend. By using this data stored inside an InnoDB table can be accessed using memcache's key-value protocol. Back in the times of the previous blog post this was limited to data from a single table, which maps easily to the key-value nature of memcache but is a clear limitation.