title: Three-way full outer join in SQLite
body: <p>I have three tables with a common key field, and I need to join them on this key. Given SQLite doesn't have full outer or right joins, I've used the <a href="http://en.wikipedia.org/wiki/Inner_join#Full_outer_join" rel="nofollow noreferrer">full outer join without right join technique on Wikipedia</a> with much success.</p>
  
  <p>But I'm curious, how would one use this technique to join <em>three</em> tables by a common key? What are the efficiency impacts of this (the current query takes about ten minutes)?</p>
  
  <p>Thanks!</p>