Advanced Relational Databases
edX
This course is one of five self-paced courses on the topic of Databases, originating as one of Stanford's three inaugural massive open online courses released in the fall of 2011. The original "Databases" courses are now all available on edx.org. This course is broad and practical, covering indexes, transactions, constraints, triggers, views, and authorization, all in the context of relational database systems and the SQL language. This course builds on concepts introduced in Databases: Relational Databases and SQL and is recommended for learners seeking to advance their understanding and use of relational databases. The Indexes and Transactions section of this course covers two important features of database systems from the application-builder's perspective: indexing for increased performance, and transactions for concurrency control and failure recovery. The Constraints and Triggers section of this course explains key, referential integrity, and "check" constraints, followed by comprehensive coverage of database triggers. The Views and Authorization section of this course provides extensive coverage of how database views can be created, used, and updated, and introduces standard techniques for authorization in relational databases.
More resources on Relational Databases
Relational Database
Master SQL database concepts with freeCodeCamp's interactive Relational Database course. Build practical projects and gain valuable skills!
MySQL 8.0 Reference Manual
The official and most comprehensive documentation for MySQL. It's an invaluable resource for understanding all aspects of MySQL, from installation and configuration to advanced features, SQL syntax, and administration. While not a traditional 'book' in print, it functions as a highly detailed and authoritative reference available online for free.
use-the-index-luke.com
A practical guide to database indexing and query optimization, offering clear explanations of how indexes work, how to design them, and tutorials with SQL examples across major relational databases.
sqlzoo.net
SQLZoo.net is an interactive SQL learning resource offering free tutorials and hands-on practice with live databases. It provides step-by-step lessons and coding exercises on SQL topics (SELECT, JOIN, aggregation, etc.) with immediate feedback.
Introduction to Database Systems (15-445/645)
Learn relational database systems from Carnegie Mellon's Andy Pavlo. Explore core concepts and implementations!
DB-Fiddle
A browser-based playground where you paste schema and query SQL, choose a MySQL, MariaDB, PostgreSQL or SQLite version, run it, and share the result by link. Useful for reproducing query behaviour and comparing engines without local installs.