Your SQL practice ground

Learn SQL through hands-on practice from your first query.

Learn SQL online on a realistic sales database directly in your browser. Run a query, inspect the result, then continue with a structured course and solved exercises.

  • No video
  • No installation
  • No account
How much revenue did each city generate? ↓
Demo database · sales6 fictional sales · amounts in euros
Available columns
villeVARCHARproduitVARCHARquantiteINTEGERmontantDECIMAL

5 minutes · no registration

Already know SQL? Start at the right level.

Get a score out of 100, see your strengths and receive a recommended path.

10 questionsTest my SQL level →

One goal, one clear starting point

What do you want to do with SQL?

Choose your goal and go straight to the most relevant practice path.

I am new to SQL

Understand SQL from scratch and complete a first query.

I want to become a Data Analyst

Analyse revenue, customers, products and trends.

I am preparing for an interview

Solve Easy, Medium and Hard series with a score.

I want to test my level

Take a quick diagnostic and receive a recommendation.

I want advanced SQL practice

CTEs, windows, transactions, indexes and PostgreSQL.

Daily SQL challenge

A short mission to keep your momentum.

One business problem, a credible dataset and a result to validate. The challenge rotates daily among published exercises.

WHERE · ORDER BYStart without an account

Filter and sort orders

Find orders over €50, from highest to lowest.

Level
Beginner
Estimated time
15 min
Solve the challenge →

Practise, understand, progress

No passive course: every concept leads to an action.

SQL.tn keeps the useful explanations, while first asking you to manipulate data and validate a result.

  1. 1

    Read the mission

    Start from a clear business question and an understandable schema.

  2. 2

    Write and run

    Test your query in an isolated lab, with no installation.

  3. 3

    Use the feedback

    Compare the result, reveal progressive hints and improve.

  4. 4

    Take the next challenge

    Save progress and move on to richer business cases.

Your momentum stays visible

Come back knowing exactly what to do next.

Your personal space brings together real progress without turning learning into a childish game.

Create my free space →

Activity streak

See active days and maintain a realistic pace.

Completed exercises

Find successes, attempts and activities worth resuming.

Next step

Continue the recommended path without searching the catalogue.

Several files, several truths

A local correction can create a global contradiction.

A spreadsheet is useful for exploring a small dataset or carrying out one-off analysis. When several teams and processes share, connect and change the same facts, a database provides common structure and rules.

See how to choose without opposing the tools →
Illustration of connected customer, order and product tables in a learning environment

Before and after

A database does not replace business knowledge: it makes facts controllable.

Before

Uncoordinated sources

  • Inconsistent names and definitions
  • Relationships that cannot be checked
  • Invisible concurrent changes
  • Reports that are hard to reproduce
With a relational database

A structured, shared source

  • Documented tables and types
  • Controlled keys and relationships
  • Constraints and transactions
  • Reproducible questions with SQL

Far more than SELECT

SQL structures, queries, changes, controls, secures and automates.

Start with six essential families. Advanced capabilities and their actual availability are documented separately.

Model

Separate customers, orders and payments without losing their relationships.

SQL · PostgreSQL

Query

Turn a business question into a reproducible result.

SQL · PostgreSQL

Change

Add, correct or remove data precisely.

SQL · PostgreSQL

Protect integrity

Reject negative prices, duplicates and orphaned relationships.

SQL · PostgreSQL

Manage transactions

Confirm or cancel several related changes together.

SQL · PostgreSQL

Create views

Reuse one shared definition across several reports.

SQL · PostgreSQL
Explore the full power of SQL

Free micro-course · 35 to 45 min

Why does SQL exist?

Understand why companies use databases, then write your first query to solve a real problem.

  • Identify the limits of uncoordinated sources
  • Distinguish database, DBMS, server and SQL language
  • Understand tables, keys, relationships and constraints
  • Connect a business need to a SQL capability
Start without an accountView terms →
01 · Spot contradictions02 · Connect the right tables03 · Choose the rules04 · Map SQL capabilities05 · Answer with SQL
38lessons
62canonical experiences
360+training variants
8business projects

Structured learning path

Follow a progressive SQL course from beginner level to a business project.

From your first query to a complete business analysis: filters, calculations, dates, aggregations, joins and CTEs.

Available

SQL Foundations

SELECTWHEREGROUP BYJOINCTE
20 lessons44 experiences in SQL Essentials62 canonical experiences remain visible across the full SQL.tn catalogue.View the beginner SQL course

Practice and business cases

Progress with solved SQL exercises and concrete analyses.

Business projectAvailable

Analyze the sales of a network of stores

Build revenue indicators from fictitious sales spread across multiple cities and channels.

  • Count sales before calculating a KPI.
  • Add all the perimeter amounts.
  • Calculate revenue by city from highest to lowest.
Create a space for the project →
View all SQL exercises →View all projects →

Focused skills

Twelve micro-courses, each focused on one practical skill.

They are available during the free 30-day beta and share progress with the learning paths, with no payment or card required.

Explore all 12 micro-courses

Launch offer

The first 50 members get all of SQL.tn free for 30 days.

SQL Pro is activated automatically, with no bank card, payment or automatic renewal.

Available with a free account

Discovery

To test the method and build your first SQL habits.

Free

  • 8 foundation lessons
  • 15 interactive exercises with solutions
  • Guided Sales Analysis project (free account required)
  • Level test and SQL environment
  • Progress linked to your account
Try for free
Access requests open

SQL Essentials

To become independent with the queries used in business analysis.

49 TND

  • 20 structured lessons
  • 44 canonical experiences
  • 36 clearly labelled training scenarios
  • 2 guided business projects
  • Solutions, hints and common mistakes
Try for free
Access requests open

SQL Analyst

For analysing business data and building reliable metrics.

99 TND

  • Everything in SQL Essentials
  • 30 cumulative lessons
  • 54 canonical experiences, including 10 multi-mission Analyst cases
  • 86 training scenarios
  • Window functions, KPIs, cohorts, data quality and SQL 50
Try for free
Access requests open

SQL Pro

For building, automating, securing and optimising with PostgreSQL.

149 TND

  • Everything in SQL Analyst
  • 62 canonical experiences, including 8 PostgreSQL laboratories
  • 118 scenarios and 360 training variants
  • Editable, resettable PostgreSQL laboratory
  • Real practice: transactions, indexes, EXPLAIN, functions, triggers and permissions
Try for free
Compare plans and terms →

Guides connected to practice

Explore a question, then move on to the activity.

View all guides →

Frequently asked questions

Before you begin.

What is SQL?

SQL is a language used by several database management systems to structure, query, modify and control data. PostgreSQL, MySQL and SQL Server are DBMSs, not synonyms for SQL.

Who is SQL.tn for?

SQL.tn is for students, career changers and professionals who want to learn SQL or strengthen their data skills.

Do I need to install software?

No. You can read lessons, view solutions, take the test and use the interactive SQL environment directly in your browser.

What does free access include?

After three activities available without an account, the free Discovery space unlocks 8 lessons, 15 exercises with solutions, the level test, SQL environment and guided Sales Analysis project. The project requires a free account to save progress.

Can I learn without programming experience?

Yes. The free Why does SQL exist? micro-course starts with conflicting files before introducing tables, relationships and the first query.

View the full FAQ →