title: DB cartesian product on same table
body: <p>I have a one column table with three rows as below:<br></p>
  
  <p>col1<br></p>
  
  <p>team1<br>
  team2<br>
  team3<br>
  team4<br></p>
  
  <p>I want to do a self cartesian join with result as below:<br>
  team1, team2<br>
  team1, team3<br>
  team1, team4<br>
  team2, team3<br>
  team2, team4<br>
  team3, team4<br></p>