PostgreSQL & MySQL
The open-source relational databases behind most web applications, and SQL practice.
Beginner
Start here. No background needed beyond school maths.
Course
Beginner
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PostgreSQL Exercises
Practice questions on a sample club database that you answer in the browser, from simple selects to window functions and recursive queries.
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Course
Beginner
↗ External site
SQLZoo
Old and loved interactive SQL tutorials with quizzes that run against real tables.
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