Case rounds
Atterna Foundations
You can write a query and want to defend the number it gives
Case rounds: Cases 2–3 · trap drills · Practice, 41 SQL tasks · Sandbox
One-time. No subscription.Data analysis practice
Start from zero or from the SQL you already know. The course’s final report and every case you finish become projects for your GitHub portfolio (free account): your SQL, the result and your decision.
A lesson screen from Start. Change the budget and watch the answer change.
Tomás: Which home products under €30 do we actually have in stock?
SELECT title, price_eur
FROM meridian.catalog
WHERE category = 'Home & Kitchen'
AND in_stock AND price_eur < 30
ORDER BY price_eur DESC
LIMIT 5
Olga: How many paid orders per promo code?
SELECT promo_code, COUNT(*) AS orders
FROM meridian.orders
WHERE status = 'paid'
GROUP BY promo_code
Vera: Which categories have the highest total order value?
SELECT s.category, SUM(o.items_total_eur) AS sales_eur
FROM meridian.orders AS o
JOIN meridian.sellers AS s ON o.seller_id = s.seller_id
WHERE o.status = 'paid'
GROUP BY s.category
ORDER BY sales_eur DESC
A practice company’s data with planted traps. You check what each number really counts, on the data.
Try a work task · 30 seconds
| week | paid orders |
|---|---|
| 1 | 2,625 |
| 2 | 2,751 |
| 3 | 3,289 |
| 4 | 406 |
Orders fell 88% in week 4. What happened?
Preparing the practice…
SQL is free: all 10 days of Start with a free account. You pay only for practice: case rounds (€19) and Meridian (€59).
Case rounds
You can write a query and want to defend the number it gives
Case rounds: Cases 2–3 · trap drills · Practice, 41 SQL tasks · Sandbox
One-time. No subscription.Includes Foundations
You already answer work questions with data
Meridian episodes 1–8 · everything in Foundations