SQL Tutorials

Learn SQL from the ground up with our comprehensive tutorials designed for beginners and intermediate users.

Beginner

15 min read

Learn what SQL is, how to install a database, and write your first queries.

SELECT * FROM customers
WHERE city = 'New York';

Beginner

20 min read

Master the SELECT statement with filtering, sorting, and basic functions.

SELECT name, age
FROM users
ORDER BY age DESC;

Intermediate

25 min read

Understand how to combine data from multiple tables using different types of joins.

SELECT u.name, o.total
FROM users u
INNER JOIN orders o ON u.id = o.user_id;

Intermediate

18 min read

Learn COUNT, SUM, AVG, MIN, MAX and GROUP BY for data analysis.

SELECT category, COUNT(*)
FROM products
GROUP BY category;

Advanced

30 min read

Master complex queries with subqueries and Common Table Expressions.

WITH sales_summary AS (
  SELECT product_id, SUM(amount)
  FROM sales GROUP BY product_id
)
SELECT * FROM sales_summary;

Advanced

35 min read

Advanced analytics with ROW_NUMBER, RANK, and other window functions.

SELECT name, salary,
  ROW_NUMBER() OVER (
    ORDER BY salary DESC
  ) as rank
FROM employees;