Database logging users out I have a CiviCRM database on a Drupal CMS using a MySQL database. I'm having problems because users keep getting logged out. First thoughts/suggestions were related to being switched between http/https, or perhaps related to Drupal modules. I've discounted all of these.

However, when I tried to deliver training to the new users (we're due to go live on 3rd April!), it only seemed to log us out when we were trying to write to the database, e.g. creating new contacts or events. Also, for a handful of contacts I hit an error when I try to view their events, but this is fine for the majority. The events were imported directly to the database using phpMyAdmin, rather than the UI in CiviCRM.

Is it possible that there's an issue with the database? I'm using MySQL v5.7. 

I'm totally out of ideas and I really need to fix this!
You cannot assume that a user stays logged in forever.  Glitches occur everywhere, especially in networks.  You must code to recover from such.

When running in a browser, each page is necessarily a separate database connection.  Code accordingly.