title: Using the value of an alias inside the same sql statement
body: <p>How can I use the value of an alias for display in the same sql statement?</p>
  
  <p><strong>For example:</strong></p>
  
  <pre><code>select now() as t, concat('Hello: ', username, t) from table;
  </code></pre>
  
  <p>What I'm actually trying to do is a lot more complex. I've broken it down to this so you get the idea.</p>
  
  <p>How can something like this be done so I neednt select the same column again?</p>