title: Joining two tables and return all records which appear in either table
body: <p>I have two tables, one which contains parts costs and another which contains labour costs.</p>
  
  <p>I would like to join these tables to show all the labour and parts costs but there are some records in the <code>Part Costs</code> table which do not exist in the <code>Labour Costs</code> table and vice versa.</p>
  
  <h3>Parts Costs Table</h3>
  
  <pre><code>Call Ref    Serial Number   Parts Costs
  1111        AB66            12
  2222        AC66            100
  3333        AD66            200
  4444        AE66            55
  5555        AF66            54
  </code></pre>
  
  <h3>Labour Costs Table</h3>
  
  <pre><code>Call Ref    Serial Number   Labour Costs
  8888        AG66            200
  1111        AB66            300
  2222        AC66            400
  9999        AH66            500
  </code></pre>
  
  <p>The result I am trying to achieve is:</p>
  
  <pre><code>Call Ref    Serial Number   Parts Costs Labour Costs
  1111        AB66            12          300
  2222        AC66            100         400
  3333        AD66            200         0
  4444        AE66            55          0
  5555        AF66            54          0
  8888        AG66            0           200
  9999        AH66            0           500
  </code></pre>