title: How does memcache with MySQL work?
body: <p>I am trying to understand (and probably deploy) memcached in our env.</p>
  
  <p>We have 4 web servers on loadbalancer running a big web app developed in PHP. We are already using APC.
  I want to see how memcached works? At least, may be I don't understand how caching works.</p>
  
  <p>We have some complex dynamic queries that combine several tables to pull data. Each time, the data is going to be from different client databases and data keeps changing. From my understanding, if some data is stored in cache, and if the request is same next time, the same data is returned. (Or I may be completely wrong here).</p>
  
  <p>How does this whole memcache (or for that matter, any caching stuff works)?</p>