title: Select query with no duplicate "First Letter" in sqlite
body: <p>How can I select data with no duplicate the "First Letter" value?
  My table has a column named "title_raw" with data arrange follow "A, B, C, ..."
  I want my data display something like this</p>
  
  <pre><code>Select (title_raw no duplicate first letter) from SONGS
  </code></pre>