title: How to select distinct values from 2 tables with sort in one query?
body: <p>I have</p>
  
  <ul>
  <li>table1 : <code>country</code>, <code>theOrderColumn1</code></li>
  <li>table2 : <code>country</code>, <code>theOrderColumn2</code></li>
  </ul>
  
  <p>I want to join DISTINCT <code>country</code> from these two SELECT statements:  </p>
  
  <pre><code>SELECT DISTINCT `country` FROM `table1` ORDER BY `theOrderColumn1`
  </code></pre>
  
  <p>and</p>
  
  <pre><code>SELECT DISTINCT `country` FROM `table2` ORDER BY `theOrderColumn2`
  </code></pre>
  
  <p>Example:</p>
  
  <p><code>table1 (country, theOrderColumn1): (uk, 1), (usa, 2)</code><br>
  <code>table2 (country, theOrderColumn2): (france, 1), (uk, 2)</code></p>
  
  <p>I want this result: </p>
  
  <pre><code>france
  uk
  usa
  </code></pre>