It turns out that the Mysql JDBC connection pool was not configured correctly.
In order to get it to work I had to set the following properties:
- User
- Password
- DatabaseName
- ServerName
- Url
- URL
I also had to repeat the database and server name in the Url and URL fields e.g.
jdbc:mysql://127.0.0.1:3306/db_name
At this point I'm not sure why there is a Url and a URL property but setting both of them to the above URL worked.