title: Delete duplicate rows on a huge list
body: <p>I have a huge list of roads and the place of that road, like below:</p>
  
  <pre><code>StreetName,PlaceName,xcoord,ycoord
  Ovayok Road,Cambridge Bay,-104.99656,69.12876
  Ovayok Road,Cambridge Bay,-104.99693,69.12865
  Ovayok Road,Cambridge Bay,-104.99794,69.12842
  Ovayok Road,Cambridge Bay,-104.99823,69.12835
  Hikok Drive,Kugluktuk,-115.09433,67.82674
  Hikok Drive,Kugluktuk,-115.09570,67.82686
  Hikok Drive,Kugluktuk,-115.09593,67.82689
  Hikok Drive,Kugluktuk,-115.09630,67.82695
  Sivulliq Avenue,Rankin Inlet,-92.08252,62.81265
  Sivulliq Avenue,Rankin Inlet,-92.08276,62.81265
  Sivulliq Avenue,Rankin Inlet,-92.08461,62.81262
  </code></pre>
  
  <p>How to delete rows that have duplicates data on first and second column? All numbers (coordinates) are differents.</p>