sequelize/sequelize — pull request #784 by sykopomp (2013-07-23 20:19:08+00:00)
Title: Optionally use environment variables with a database URL to configure mi...

...grations

The following config/config.json would work with heroku:

```json
{
"development": {
"username":"username",
"password":"password",
"database":"db",
"host":"127.0.0.1",
"dialect":"postgres",
"protocol":"postgres"
},
"production": {
"use_env_variable": "DATABASE_URL",
}
}
```

Provided you've set up the database and configured ```NODE_ENV=production``` on heroku.