Run app locally with Heroku

You use your app locally for testing purposes, make sure you already have PostgreSQL installed. You then need to create the Postgres database for development. Open up config/database.yml. Find the block that says "development" and then take note of the value of the "database" property. You'll need to create a Postgres database locally that has the same name. You can do this using createdb, which comes prepackaged with PostgreSQL.

createdb