Syllabus & Study Plan

What the SQL course covers, what you'll be able to do by the end, and a suggested eight-week schedule with a checkpoint each week. Every lesson has live editors connected to the same demo database, so plan time to experiment.

Who this course is for

Beginners with no database experience, developers who use an ORM and want to understand the SQL underneath, and analysts, product managers and marketers who want to answer their own data questions.

Learning outcomes

By the end of the course you will be able to:

  1. Write queries that select, filter, sort and limit data, handling NULL correctly.
  2. Transform values with text, number, date and conversion functions and CASE.
  3. Summarise data with aggregates, GROUP BY, HAVING and pivot-style reports.
  4. Combine tables with every kind of join and set operation, and avoid duplicate-row mistakes.
  5. Solve multi-step problems with subqueries, CTEs, recursive queries and window functions.
  6. Change data safely with INSERT, UPDATE, DELETE, upserts and transactions.
  7. Design normalised tables with appropriate types, constraints, keys, indexes and views.
  8. Read query plans, write index-friendly queries and prevent SQL injection.
  9. Move between SQLite, PostgreSQL, MySQL, SQL Server and Oracle with awareness of their differences.

Course outline

PartLessonsFocus
1. Getting Started01–08SELECT, WHERE, logic, ORDER BY, LIMIT, DISTINCT
2. Filtering & Expressions09–13IN, BETWEEN, LIKE, NULL, CASE, operators
3. Functions14–17Text, numbers, dates, CAST
4. Grouping & Aggregation18–21Aggregates, GROUP BY, HAVING, conditional aggregation
5. Joins & Set Operations22–28Keys, all join types, UNION/INTERSECT/EXCEPT
6. Subqueries, CTEs & Windows29–34Subqueries, EXISTS, WITH, recursion, window functions
7. Changing Data35–39INSERT, UPDATE, DELETE, upsert, transactions
8. Database Design40–47Tables, types, constraints, keys, normalisation, indexes, views
9. Advanced & Practical48–53Triggers, JSON, security, performance, dialects, project

Eight-week study plan

Plan on three to four hours a week.

Week 1 — First queries

Lessons 01–08.

Checkpoint: without looking back, list the five cheapest products in stock, and the countries customers come from.

Week 2 — Filters and functions

Lessons 09–17.

Checkpoint: produce a customer list with a cleaned-up display name, the email domain, a "missing data" label and days since sign-up.

Week 3 — Aggregation

Lessons 18–21.

Checkpoint: a monthly report with one column per order status, and the categories whose average price exceeds 30.

Week 4 — Joins

Lessons 22–28.

Checkpoint: every customer with their order count and total spend (including customers with no orders), and an org chart of employees with their managers.

Week 5 — Subqueries, CTEs and windows

Lessons 29–34.

Checkpoint: the top two products per category, a running revenue total by month, and the full management chain above any employee.

Week 6 — Changing data

Lessons 35–39.

Checkpoint: in one transaction, place a new order with two items and reduce stock; then repeat with an error and roll back.

Week 7 — Database design

Lessons 40–47.

Checkpoint: design and create normalised tables for a small library (books, authors, members, loans) with keys, constraints, an index and a reporting view.

Week 8 — Advanced topics and the project

Lessons 48–53.

Final project: complete all nine analysis tasks before opening the solutions, then take the quiz and aim for 25 out of 30 or better.

Faster tracks

  • Data analysis focus (about four weeks): Parts 1–6 plus lessons 47 and 53.
  • Developer focus: add Parts 7–8 and lessons 50–52 — transactions, design, security and performance matter most when building applications.
  • Already write SQL? Take the quiz first, then concentrate on lessons 11, 24, 27, 30, 33–34, 39, 46 and 50.

Practice resources

  • Playground — a free editor connected to the demo database.
  • Exercises — 34 fill-in-the-blank tasks and six query challenges.
  • Quiz — 30 questions with explanations.
PreviousQuiz