title: sql query distinct on multiple columns
body: <p>i have this data and i am trying to find cases where there are different ids but duplicate data in Field 1,2,3,4</p>
  
  <pre><code>id    field1 field2 field3 field4    
  ====  ====== ====== ===== =======    
  1       A      B     C      D    
  2       A      B     C      D    
  3       A      A     C      B   
  4       A      A     C      B
  </code></pre>
  
  <p>so, in whatever way possible, in this case i want it to somehow show me:</p>
  
  <p>1 &amp; 2 are duplicates
  3 &amp; 4 are duplicates</p>