FreeSQL Foundations — your first real data skill. Start querying for free today. Start SQL →
SQL Domain

MASTER
SQL.

» SQL is the most universally required data skill. Pick your track — Foundations, Analytics, or Backend — and go from zero to professional queries.

✓ Free starter course✓ In-browser SQL editor✓ PostgreSQL✓ Real datasets✓ Certificates
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Who needs SQL?

Data Analysts

SQL is your primary extraction and reporting tool. Every analytics role expects it.

Backend Developers

You will work with databases daily. Schema design, CRUD, and query optimisation are core developer skills.

Product & Ops People

Being able to query your own data makes you 10x more effective than people who have to wait on engineers.

Choose Your Track

3 Tracks. One Domain.

Everyone starts at SQL Foundations. After that, you branch based on your goal.

★ Start Here
Beginner
Entry Track

SQL Foundations

Learn the essential SQL skills needed to query, summarise, and combine relational data with confidence.

SELECT, WHERE, ORDER BY
Aggregate functions
JOIN all types
CASE WHEN
CTEs & Subqueries
4 courses·~35 hrs·SQL Foundations Badge
Analyst
Analyst Track

SQL for Data Analysis

Use SQL to build reports, answer business questions, and generate decision-ready insights.

KPI queries
Window functions
Cohort & segmentation logic
Data cleaning in SQL
LAG, LEAD, RANK
5 courses·~45 hrs·SQL Data Analyst Badge
Developer
Developer Track — Coming Soon

SQL for Backend Developers

Learn how developers use SQL in application systems, schemas, CRUD workflows, and transactions.

Schema design
CRUD with SQL
Keys & constraints
Transactions & ACID
Query performance basics
5 courses·~30 hrs·SQL Backend Developer Badge

Recommended Learning Routes

I want to learn SQL from zero
  1. 1SQL Foundations: Core Queries
  2. 2Data Transformation
  3. 3Joins & Relationships
  4. 4Subqueries & CTEs
→ Earns: SQL Foundations Badge
I want to work as a data analyst
  1. 1SQL Foundations Track (all 4 courses)
  2. 2SQL Window Functions
  3. 3Python for Data Analysis
→ Earns: SQL Data Analyst Badge
I want to build backend systems
  1. 1SQL Foundations Track
  2. 2SQL for Backend Developers (coming soon)
→ Earns: SQL Backend Developer Badge
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Start with SQL Foundations. It's free.

The first course — SQL Foundations: Core Queries — is completely free. No credit card. No account wall on lesson 1. Just open and start querying.