title: Multiple ID's in a field. Postgresql
body: <p>So, i'm currently working with a database system where a user can register, login and update his/her details whenever.
  The database includes 5 roles:</p>
  
  <pre><code>1. Public
  2. Member
  3. Moderator
  4. Coordinator
  5. Admin
  </code></pre>
  
  <p>I want to be able to assign multiple roles to my users. For example, the Admin can also be a member. Therefore in the database it should show:</p>
  
  <pre><code>User_id    |    Role_ID
  ------------------------
  user1      | 2, 5
  </code></pre>
  
  <p>^ is it possible to add multivalued id's in postgresql?</p>