title: Using Parse, how do I set a column unique or at least check if it exists first?
body: <p>I have a table of 'words', and what I want to do is, if a user uses that word, insert it into the table. But, if it already exists, update the count on that word.</p>
  
  <p>I don't see a way to actually set columns as unique..
  That said, how do I avoid the race condition:</p>
  
  <p>t1 - user1 checks if 'Love' is used. NO
  t2 - user2 checks if 'Love' is used. NO
  t3 - user1 adds 'Love'
  t4 - user2 adds 'Love'</p>
  
  <p>I do not want this to be in the database twice.  Anyway to accomplish this in Parse?</p>