There are lots of choices. Ruby on Rails is a famous choice in the US/England for fast development of websites. PHP is the most famous one for Indian startups (I think its mostly because of the number of people). There are many things that lead you to take the programming language for a startup / project lead.
The ** Cart** on an e-commerce websites is the most important of all along with the **Wishlist**. Amazon.com used to use DynamoDB (not sure if they still do) for saving the shopping cart across millions of users. Simple: If you lose items from the cart, you lose the customer. You cannot show old data. (The paper on DynamoDB published in 2007 was famous because of the architecture it uses. DynamoDB is currently offered as a service as part of AWS).