SQL
SELECT, WHERE, JOIN, GROUP BY, then window functions, views and your own tables.
Foundations is free: 7 lessons.
39 lessons, 7 free
0 of 39 lessons passed
SQL COMPLETE
You can now:
- Answer real questions from a database on your own
- Join, group and summarise data across several tables
- Break hard questions into steps with CTEs and window functions
- Design tables with keys, constraints, views and indexes
- Change data safely with transactions
- Find and fix queries that run and still give the wrong answer
Practise
The course, unit by unit
Part 1: Foundations
1 unit, 7 lessons
Part 1: Foundations
1 unit, 7 lessons
Part 2: Core
1 unit, 11 lessons
Part 2: Core
1 unit, 11 lessons
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Unit 2: Core
5 hr 15 minBrainlag Code
- NULL and missing values in SQL, Brainlag Code
- SQL COUNT, SUM and AVG, Brainlag Code
- SQL GROUP BY and HAVING, Brainlag Code
- SQL CASE WHEN, Brainlag Code
- SQL checkpoint: summing upCheckpoint, Brainlag Code
- SQL JOIN: combining two tables, Brainlag Code
- SQL LEFT JOIN, Brainlag Code
- Joining three or more tables in SQL, Brainlag Code
- SQL self join, Brainlag Code
- SQL checkpoint: joinsCheckpoint, Brainlag Code
- SQL INSERT, UPDATE and DELETE, Brainlag Code
Part 3: Deeper
2 units, 21 lessons
Part 3: Deeper
2 units, 21 lessons
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Unit 3: Advanced
9 hr 15 minBrainlag Code
- SQL subqueries, Brainlag Code
- SQL EXISTS and correlated subqueries, Brainlag Code
- SQL WITH and common table expressions (CTEs), Brainlag Code
- SQL UNION and UNION ALL, Brainlag Code
- SQL window functions: ranking rows, Brainlag Code
- SQL running totals and LAG, Brainlag Code
- SQL checkpoint: the film siteCheckpoint, Brainlag Code
- SQL transactions, Brainlag Code
- SQL CREATE TABLE and constraints, Brainlag Code
- Database normalisation, Brainlag Code
- SQL views, Brainlag Code
- SQL indexes and query plans, Brainlag Code
- SQL with an AI assistant, Brainlag Code
- SQL bug huntBug hunt, Brainlag Code
- SQL final challenge: the film databaseFinal challenge, Brainlag Code
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Unit 4: Real-world analysis
3 hr 15 minBrainlag Code
Projects
Lessons teach one idea at a time. Projects glue them together: a brief, a few milestones and a starter file.
- Festival planner40 min, 5 milestones
- Brainlag Code: Playlist stats30 min, 3 milestones
- Brainlag Code: Tuck shop sales35 min, 3 milestones
4 more projects
Bigger builds included in Brainlag Code
Questions
What is the course about?
Ask data questions. SELECT, WHERE, JOIN, GROUP BY, then window functions, views and your own tables. Ask real data questions and see how apps remember things. It is for: beginner.
What is free?
7 of the 39 lessons.
Do I need to install anything?
No. Your code runs in the browser, in the editor beside each lesson.
Do I need an account?
No. Progress saves in this browser; sign in to keep it on every device.
What can I do by the end?
- Answer real questions from a database on your own
- Join, group and summarise data across several tables
- Break hard questions into steps with CTEs and window functions
- Design tables with keys, constraints, views and indexes
- Change data safely with transactions
- Find and fix queries that run and still give the wrong answer
How long does it take?
About 20 hr 45 min of lessons in 4 units. Lessons take 25 to 60 minutes each.