Learn SQL
Free SQL guides, practice sets, and explainers — from basic queries to advanced techniques.
Whether you're a complete beginner or preparing for a data analyst interview, these resources cover the SQL concepts and query patterns that come up most in the real world.
Practice Sets
Practice Set
15 SQL JOIN Practice Problems with Solutions
15 beginner-friendly JOIN exercises covering INNER JOIN, LEFT JOIN, and multi-table JOINs with full solutions and explanations.
Practice Set
15 SQL GROUP BY Practice Problems with Solutions
15 beginner-friendly GROUP BY exercises covering COUNT, SUM, AVG, HAVING, and ORDER BY with full solutions and explanations.
Practice Set · Beginner
20 SQL Practice Problems for Beginners with Solutions
20 beginner SQL problems covering SELECT, WHERE, ORDER BY, LIMIT, and COUNT — with plain-English explanations for every solution.
Practice Set · Beginner
15 SQL WHERE Clause Practice Problems with Solutions
15 beginner-friendly WHERE clause problems covering text filtering, numeric comparisons, combining with ORDER BY, and AND/OR conditions.
Practice Set · Intermediate
15 SQL Subquery Practice Problems with Solutions
15 intermediate subquery problems covering WHERE with comparison operators, IN and NOT IN, and subqueries in FROM as derived tables.
How-To Guides
Error Explainers
Interview Prep
Looking for interactive practice? Head back to the SQL Drills homepage to write and submit real queries with instant feedback.