It can be really useful when working locally to use Mamp’s database it’s very easy to setup new databases and manage them. By default Nova probably won’t be able to connect to the database unless you map a project from Mamp. In my case I like to install Nova Framework into a folder open terminal run a server and use Mamp for the database only.
All you need to do to solve this is to open app/Config/Database.php and add the following to your mysql array:
'unix_socket' => '/Applications/MAMP/tmp/mysql/mysql.sock',
Then you can use Nova from the command line / built in server and manage the database with Mamp / Sequel Pro.