Personalized SQL interview practice

SQLQuest.app — personalized SQL interview practice.

An AI coach that finds your SQL skill gaps — and builds your practice around them.

5,745 accepted solutions · 1,195 people last 30 days

Every query you solve scores your Skillmap across nine SQL skills. The coach reads it, picks your next question from the weakest line, and tells you why a wrong query is wrong. Company sets and timed mocks for the screen you have. 299 challenges. Start free.

Start free See pricing

Skillmap

Nine SQL skills, scored as you solve

Your next question

Picked from your weakest skill

Company sets & mocks

Capital One · Revolut · Stripe · Wise

neobank_screen.sql
1
2
3
4
5
6
SELECT plan,
       COUNT(*) AS users,
       ROUND(100.0 * SUM(declined) / COUNT(*), 1) AS decline_rate
FROM transactions
GROUP BY plan
ORDER BY users DESC;

✓ 3 rows returned (0.002s)

planusersdecline_rate Standard1,2044.1 Premium3882.6 Metal971.9
Correct — row set matches+25 XP
Skillmap

Your Skillmap finds the gap. The coach closes it.

Most SQL sites hand you a list. SQL Quest scores every solve on nine skills — joins, window functions, aggregation, CTEs and five more — so you see exactly where you would lose points in an interview. The coach picks the next question from your weakest line, and a wrong submit gets a diagnosis, not "incorrect".

Just now: Hard Window challenge solved · +5 Window Functions
sqlquest.app/app · Coach
YOUR GOAL
SQL Fundamentals Mastery
Change goal
Step 13 of 27 48% complete
YOUR NEXT STEP
Solve 3 fresh Medium+ GROUP BY challenges
Why: you finished the GROUP BY lesson yesterday. Time to prove you can produce, not just recognise.
STEP TYPE · MASTERY CHECK
Challenge #100 — "GROUP BY Basics"
Medium GROUP BY Aggregation ~4 min
UP NEXT · RETRIEVAL CHECK
Solve a GROUP BY problem from cold memory
Tomorrow · spaced retrieval
Pricing

Pro is the interview, run before the interview.

Free gets you practising today. Pro is for the weeks before a named screen: the questions it saves for last, the clock, and help that does not run out.

Solve the Hard question on the day
Screens save one shape for last: a window function over a ledger, a NULL nobody handled. The Hard set is that shape, all of it.
Sit the screen before you sit the screen
The timed mock bank, including the 60-minute Revolut and 70-minute Capital One formats. Walk in already knowing the clock.
Never stall the night before
The tutor reads your wrong query and your history and stays with you. Pro lifts the free tier's daily cap.
Save 72%
$99
a year
$8.25 a month, billed yearly · most people choose this
Choose annual →
$29
a month
Billed monthly · cancel anytime
Choose monthly →
Start free

Upgrade inside the app when a screen has a date. Cancel anytime; 7-day full refund on both plans.

Company interview sets

Pick the company. Get its set, then its screen.

Each set is tagged from what candidates report: the tables, the tasks, the time. Two companies also have a timed mock built to the reported format. Every company page dates its sources.

RRevolutOpen →
60-min analyst screen mock · 6 MCQ + 2 written SQL, HackerRank-style
Users, top-ups and transactions in 12 currencies: MAU, top 10% by volume, decline rates by plan.
CCapital OneOpen →
70-min CodeSignal-style mock · 8 MCQ + 6 written SQL
Accounts, merchants, transactions, chargebacks: the reported data analyst screen, both halves.
SStripeOpen →
Tagged set · timed practice
Payments and revenue tables: duplicate transactions, MRR movements, failed-charge retries.
WWiseOpen →
Tagged set · timed practice
Cross-border transfers: FX corridors, margin per route, settlement timing.
JJPMorganOpen →
Tagged set · timed practice
Financial analytics and risk: running balances, exposure by counterparty, month-end positions.
SnSnowflakeOpen →
Tagged set · timed practice
A Snowflake-compatible practice set plus the patterns warehouse teams ask.

More company pages: Plaid · Ramp · Morgan Stanley · Spotify · Amazon · Google · Meta · Apple · Netflix · Uber · Airbnb · Shopify · Databricks · NVIDIA · OpenAI · Anthropic · Tesla · Interview Prep Hub →

Formats and topics come from candidate reports on Glassdoor, Blind and forums, dated on each page; the questions are SQL Quest's own, matched to those topics — not questions any company has published. No set is affiliated with or endorsed by the company it is named for, and screens change — treat every specific as reported, not official.

299 SQL practice challenges, each tagged on the Skillmap — window functions, joins, CTEs, aggregation, subqueries, CASE, dates, NULLs, strings.

Browse the whole bank →
How it stacks up

The tutor features the question banks don't have

Most SQL sites hand you a list of questions and leave you to guess what comes next. SQL Quest tracks where you actually get stuck, explains why a query is wrong, and picks your next challenge from your own weak spots.

Feature SQL Quest DataLemur StrataScratch HackerRank LeetCode DB SQLBolt
Explains why your query is wrong ✓ — — — — —
AI Coach with contextual memory ✓ Claude — AI evaluator — — —
Skillmap that picks your next question ✓ — — — — —
Company-tagged challenges ✓ by company ✓ ✓ partial — —
Substantial free tier ✓ partial ✓ ✓ ✓ ✓

Checked September 2026 against each site's public pages (LeetCode: April 2026 — its site blocks automated reads). Competitor features change; tell us if a row is stale.

Built in public

Every feature is built on what real users tell me

I teach SQL 1:1 on Preply. Watch students get stuck in real time, ship fixes same-day. Pro users DM on LinkedIn, get replies within hours. Last week:

Same-dayPreply student, data analyst

Wrong-answer diagnostics

"I submitted my query and the grader just said 'incorrect'. I had no idea what was wrong."

Shipped: a nine-category diagnostic that names the gap in plain English on every failed submit.

Next sessionPreply student, BI analyst

Show Structure hints

"I know CASE WHEN exists but I keep putting it in the wrong place."

Shipped: skeleton templates that show where each clause lives, without giving the answer.

Same week1:1 lesson with manufacturing engineer

"Started" badge + Previous button

"I opened a challenge, got pulled into Slack, came back and couldn't tell which one I was already mid-way through."

Shipped: a "Started" badge and filter, plus a Previous Question button.

Friction reported → fixed same day. Every week. You benefit.

Your interview has a company name.
So does your practice.

No signup. No card. First query in under 60 seconds.

Start free

Runs in your browser. No install, no plugins.

Frequently Asked