title: How do I save a field in a model without persisting it in db?
body: <p>I'm very new to Spring Boot so this is probably a n00b question. </p>
  
  <p>I'm trying to save a field (table number) that is only accessible if a user is logged in. I do not want to persist this in the database.</p>
  
  <p>flow:
  - log in
  - select table 
  - save table number for current user
  - do stuff that needs the table number
  - log out
  - forget table number. </p>
  
  <p>I tried using @Transactional to prevent saving the field and using the SecurityContextHolder.getContext().getAuthentication to get the current user.
  Doing this I can save the field. If I later use the same way of getting the current user and calling the getTableNumber() method the field is not set anymore.</p>
  
  <p>I realise this is probably a very simple thing to do, but I'm having some problems understanding how to access models without accessing my database. </p>
  
  <p>If more explanation or actual code is needed let me know.</p>