Working on a rails application and a spring server is started with DATABASE_URL
environment variable set, both development and test environments connect to that database. My test setup has a database wipe between tests.
I was using guard to run my tests, which made the initial diagnosis challenging.
- DATABASE_URL has special meaning for Active Record - it overrides any other configuration. This is tacitly understood - heroku will setup DATABASE_URL as an environment variable - but it is explicitly mentioned in the edge guides (describing v6).