title: sql, multiple instances of the same table in FROM
body: <p>Let's say I have a table named "mytable01". When I want to have  two instances of the table in the query I do this:</p>
  
  <pre><code>SELECT t1.column, t2.column
  FROM mytable01 t1, mytable01 t2;
  </code></pre>
  
  <p>Now, there are times that I want two instances from the same nested SELECT. Is there a way to do it without having to write it two times?</p>