Master the art of data storage and retrieval. Learn the industry-standard RDBMS (MySQL) and the leading NoSQL database (MongoDB), and test your skills with our curated questions.
The world's most popular open-source relational database. Learn about Tables, SQL Queries, Joins, and Normalization.
A leading NoSQL database. Learn about Collections, Documents, JSON-like schemas, and Aggregation.
Prepare for interviews with a comprehensive list of SQL questions, answers, and query optimization tips.