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Platform Features

Basic SQL
≈ 2 min read

Theory, practice, and progress — all in one place

On the course page, choose an SQL topic and move through it from top to bottom. Nested materials can be expanded directly in the roadmap, and completed pages can be marked as finished. Once you sign in, your progress is saved automatically.

Marking a page as completed

Practice right after the theory

After studying a construction, move on to exercises for the same topic. You can solve them from the course page or through the separate “Practice” section. In Ranked mode, you complete exercises, advance the topic progress, and earn rating points. The Exam lets you check your knowledge separately with a random set of exercises and does not affect your rating.

Simply fixing an incorrect SQL query is not always enough. Try to understand at which stage the result stopped matching your expectations: rows were filtered incorrectly, tables were joined incorrectly, or aggregation changed the data differently from what you expected.

Track your progress

Your profile contains statistics for theory and practice. They help you quickly see which parts of SQL you already understand confidently and which topics are worth revisiting before moving on.

Statistics in the profile

Interview preparation

The “Questions” section contains questions from technical interviews. You can filter them by topic and company, so you can separately review JOINs, indexes, transactions, isolation levels, and other SQL topics.

Technical interview question database

Premium unlocks advanced platform materials, including detailed solutions to interview questions.

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