If we are working with rails version 2.X.X , the rails framework automatically create an application with sqlite as a default database. If we want to create the rails application with our selected database by using the following command..
Syntax : rails -d database_name app_name
Example :
rails -d mysql depot (OR) rails shopping_cart -database=mysql
Here, depot and shopping_cart are the application names which we are going to create for rails.