MongoDB Data Modeling

Where should a customer's address be stored: inside the customer document, or in another collection with a link between the two? Questions of this kind are data modeling, which is the work of deciding how documents and collections are structured so that the application can read and write its data efficiently.

A relational database usually spreads this data across several tables with a fixed set of columns. MongoDB does not require every document in a collection to have the same fields, so the structure can change as the application changes