18
Week of 2026-W18 SQL Challenge of the Week

The SQL Challenge
that drops every Monday.

Solve it in your browser. Share your time. Come back next week. 72 challenges in rotation, picked deterministically each week — same challenge for everyone, no leaderboard gaming.

Easy

Counting Rows

Answer three questions about the passengers table in a single query: How many total passengers are there? How many survived? How many have a known age (age is not NULL)? Name the columns total, survived, and known_age.

▶ Start Challenge No signup. Browser-based SQL editor. AI Coach if you get stuck.
📅 Coming Monday — Week 2026-W19
Next up: SUM, AVG, MIN, MAX

📚 Recent Weeks

Past challenges are still solvable in the app. Each week's pick is deterministic, so anyone visiting that week sees the same challenge — fair time comparisons.

Why a weekly challenge?

Practicing SQL works the way going to the gym works: a small, predictable habit beats heroic sprints. 15 minutes every Monday for a year is enough to clear most data-analyst SQL interviews. A scattered hour-here-and-there approach plateaus around month 2.

The Weekly Challenge is the ritual. Same time every week, fresh problem, no decision fatigue. Solve it, share it if you want to, come back Monday. The 200+ practice bank is here when you want unlimited; the weekly is for when you want a single committed rep.

Want more than one a week?
200+ challenges, all free tier.

SQL Quest's free tier covers Easy/Medium/Hard across the full bank, plus the AI Coach with a daily quota.

Open SQL Quest — Free ⚡

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