This might help. The config/database.yml handles relational databases.
The config/dynamodb.yml handles dynamodb. Did it this way so people can run both databases if required.
Here’s also an example project: https://github.com/tongueroo/jets-dynamodb-example
Also, want to say that running dynamodb locally is a little bit tricky since it assumes you have AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY set. It’s quirky if you are using `AWS_PROFILE.
This thread also has some helpful details: Running rspec over dynomite model with local dynamodb instance results in MissingCredentialsError