title: Selecting distinct 2 columns combination in mysql
body: <p>I have a mysql table that looks like this:</p>
  
  <pre><code>1   value1    value2    3534
  2   value1    value1    8456
  3   value1    value2    3566
  4   value1    value3    7345
  5   value2    value3    6734
  </code></pre>
  
  <p>I need a query to select all the rows with distinct column 2 and 3, for example the output I want for this example will look like this:</p>
  
  <pre><code>1   value1    value2    3534
  2   value1    value1    8456
  4   value1    value3    7345
  5   value2    value3    6734
  </code></pre>
  
  <p>i've found a few samples on how to do it but they all select distinct on each column individually.</p>