I'm relatively new to RoR and I am facing this problem.
To give you all guys a little of context on this issue, let me tell you my story. Turns out that for example today I ran my rails unit tests for a project I work for, I am starting to create and play around a little with unit tests. In the morning they perfectly ran, all my tests passed, so I kept working on a new feature and when it was time after I made changes I tried to run my unit tests again to make sure I did not break anything.. And Boom! I typed the command, hit enter, the console took a while and after some time Rails told the database no longer exists. This has happened since I started to work on this project, approximately 1 year now. After I got that error I need to create again the database and migrate again all tables in order to test :(
I have researched but found nothing that can help me sort this out.
I'm using Rails 5.2, Ruby 2.3.1, Ubuntu 16.04, mysql