Most database design challenges are about taking a real life problem, abstract it into a model with entities and relationships, and represent it in a database correctly. Most of the time, these challenges will be on a relational databse.
A good design takes into account an intuitive and useful model, the scalability of the design, and the technical decisions related to the database technology used.
Use https://excalidraw.com/ to diagram and explain a design.
-
Model a neo-bank application. This system will allow users to make deposits and withdrawls, and use the balances to purchase investment products.
-
Design a real estate listings application. How would you handle media and metadata? How would you handle a large volumen of content as well as duplicated ads for the same system?
-
Model a movie theatre ticketing system. This system will be the backbone to allow users to purchase tickets. It must support ticket availability, timezones, theatre seat charts, pricing.
-
[Hard] Model a ride-sharing service like Uber. How would you handle matching passangers to drivers? Take into account location and pricing.