title: Returning 2 columns from the same field? [Oracle]
body: <p>I've a Databases exam coming up so I'm doing a past paper on the subject. The language we are using is Oracle. I'm considering this study so please don't think I'm asking for homework answers. I've been trying to get my head around this for a while.</p>
  
  <p>The case study is a city bike rental scheme. Here is the database the question is based on:</p>
  
  <p><img src="https://i.imgur.com/3bFDEA4.png" alt="scrshot"></p>
  
  <p>The question states: Write an SQL statement to return all possible pairs of station locations (station.locatn) a cyclist might use - eg. "Bolton Street", "Charlemont Place". Your results should only show each pair once ie. "Bolton Street", "Charlemont Place" should not appear in the same result set.</p>
  
  <p>So from this I gather that I have to return 2 columns where each row consists of 2 locations from the station.loctn field and each pair may only appear once. How do I return 2 columns of the same field?</p>