title: How are left join, inner join, union of mysql can be replicated in redis
body: <p>I think cross referancing is a good way of learning. I made some research on redis and it seams that as a schameless database redis don't have tables. Instead of tables it has got key-value, key-list, key-set and key-sortedset(zset) pairs.</p>
  
  <p>This kind of key-data pair structure is too unfamiliar for me. I'm more used to mysql, sql styled databases.</p>
  
  <p>I got a sqlFiddle <a href="http://sqlfiddle.com/#!2/125ab/3" rel="nofollow">here</a> it demonostrates a simple inner join example. </p>
  
  <p>I offenly take this data from sql and re-model it to a meaningfull JSON object like this:</p>
  
  <pre><code>var posts = {
      users: [{
          userid: 1,
          posts: [{
              header: "header1",
              content: "content of header1"
          },{
              header: "header2",
              content: "content of header2"
          },{
              header: "header3",
              content: "content of header3"
          }]
      },{
          userid: 2,
          posts: [{
              header: "header4",
              content: "content of header4"
          }]
      }]
  }
  </code></pre>
  
  <p>My question is: </p>
  
  <p>How can I mimic this kind of table structure on redis and node.js?
  Is there a build in redis command for foraign keys?
  If I have no option but using app level data re-modeling how is the proper way to doing that kind of process.</p>
  
  <p>PS: Cross referancing examples and usefull articals would be apriciated.</p>
  
  <p><strong>EDIT:</strong>
  Is join like operations can be done by SINTER command of Redis? </p>