title: Updating entries in a database based on time
body: <p>I have a model called "ticket" that has a start time and end time. I would like to be able to sort/divide tickets by time on the front-end. There will be 3 categories: past (now > end_time), current (start_time &lt; now &lt; end_time), future (now &lt; start_time). Where now represents the real UTC time. I am thinking of having a "state" field in the ticket model which will contain the value "past", "current", or "future". I need a way to update the state of tickets based on time. </p>
  
  <p>Would a cron job running every minute be an appropriate solution for this? It will iterate through all entries and do a check if the state should be updated and then perform the update if necessary. Is this solution scalable? Is there a better solution?</p>
  
  <p>If it is necessary info I am thinking of using Firebase for the database and Google App Engine for the cron job.</p>