Leaderboard Engine
Build the ranking machine behind every leaderboard: ranks, ties, percentiles, and exactly who is one spot ahead of you, all with window functions.
What you'll be able to build
Build the ranking machine behind every leaderboard: ranks, ties, percentiles, and exactly who is one spot ahead of you, all with window functions. Along the way you pick up real, transferable SQL skills, not just this one project:
- GROUP BY aggregation to compute per-entity scores
- ROW_NUMBER vs RANK vs DENSE_RANK (and how ties differ)
- PARTITION BY to rank within groups
- LAG / LEAD to compare a row to its neighbors
- Running totals with SUM() OVER (ORDER BY ...)
- Filtering on a window result via a CTE (top-N-per-group)
A course like this one
Yours is built from your own placement, so module count and depth will differ. This map shows what a advanced-level SQL learner building Leaderboard Engine actually gets.
- Module 1: Advanced Tables, Rows, and Query Intent5 lessons
Builds the production-ready version of the table model for your leaderboard engine.
- Module 2: Advanced Reusable Query Patterns5 lessons
Builds the production-ready version of the reusable query helper for your leaderboard engine.
- Module 3: Advanced Transactions and Data Boundaries5 lessons
Builds the production-ready version of the transaction boundary for your leaderboard engine.
- Module 4: Advanced Joins, Groups, and Data Shape5 lessons
Builds the production-ready version of the join shape workflow for your leaderboard engine.
- Module 5: Advanced Filters, Conditions, and Result Sets5 lessons
Builds the production-ready version of the filter rule that powers your leaderboard engine.
- Module 6: Advanced Reliable Reporting Queries3 lessons
Builds the production-ready version of the report query for your leaderboard engine.
How the lessons actually work
Every lesson has you predict what a piece of SQL code will output before you run it, then run it for real in your browser and fix what you got wrong. Each module ends in a challenge gate with hidden tests, so you can't advance until your code actually works. The course closes with a capstone that assembles everything into Leaderboard Engine, and a runnable proof page tied to your own code.
Common questions
How long does the Leaderboard Engine course take?
about 7 hours, across 6 modules and 28 lessons, at roughly 15 minutes per lesson. Your own course may run shorter or longer, since it's sized to your placement result, not a fixed template.
Do I need experience?
Yes. This is an advanced-tier SQL project, so it assumes you're already comfortable writing and reading SQL before you start.
How much does it cost?
$15 one-time, no subscription. The first module is free, so you can see exactly how the course teaches before you pay for the rest.