title: how to run UNIONALL query in BIGQuery
body: <p>I'm encountering following error while running <code>UNIONALL</code> query in Bigquery compose query console(web-UI).</p>
  
  <p><code>Encountered " &lt;ID&gt; "UNIONALL "" at line 23, column 10. Was expecting: &lt;EOF&gt;
  </code></p>
  
  <p>All I'm running the following query</p>
  
  <pre><code>SELECT 2 AS y 
  UNIONALL
  SELECT 1 AS y;
  </code></pre>
  
  <p>How can I manage to run this above query.. </p>
  
  <p>I have checked and unchecked <code>Use Legacy SQL</code> checkbox multiple times but no gain here.</p>