title: How can I compare rows from 2 tables that have composite primary keys?
body: <p>Here's the scenario:</p>
  
  <p>I have 2 tables with data, one is the 2009 version and the other is the 2010 version. The primary key for each of the tables is a composite key. I know there is a different number of rows in each one and I need to find out the differences.</p>
  
  <p>Typically, in the "normal" primary key set-up, I would just look for primary key values NOT IN the list of primary keys from the other table. But I don't know how to do this with a composite primary key (or even if it's possible).</p>
  
  <p>So, how can I compare the rows from these two tables?</p>
  
  <hr>
  
  <p>EDIT: More specifically, I am trying to find the <em>difference</em> between the tables, rather than the rows in common</p>