About this product

THE HEADLINE

Walk into the live SQL round with patterns rehearsed, not just syntax memorized — 40 concept drills, 30 real problems on a real runnable database, and narration scripts for thinking out loud.

WHO THIS IS FOR

• Aspiring and junior data analysts preparing for SQL interviews
• Career changers who know basic SQL and need interview fluency fast
• Anyone who has frozen on a window-function or "top-N per group" question

THE PROBLEM

Data analyst interviews have a brutal filter: the live SQL round. Candidates who know SQL "well enough" freeze when asked for top-N per group, blank on window functions, or write a query that runs but answers the wrong question. Tutorials teach syntax; interviews test thinking under pressure — and most prep material never lets you run a single query.

THE SOLUTION

A playbook built the way interviews actually work. You drill the 40 concepts interviewers really ask about, work 30 real problems against a real database (the same one behind every problem in the book), and practice narrating your thinking out loud — which is half your score in live interviews.

WHAT'S INCLUDED (exact files)

• Query-Ready-SQL-Playbook.pdf (46 pages): Part 1 — how SQL interviews work (the 4 formats, what interviewers score, 2-week study plan, minute-by-minute anatomy of a 45-minute interview, reading EXPLAIN, what to do when stuck, red flags). Part 2 — 40 concept drills, each with a model answer and a "say it in the interview" line (execution order, JOINs, NULLs, COUNT pitfalls, GROUP BY/HAVING, DISTINCT, UNION, subqueries vs CTEs, window functions, CASE, dates, LIKE, keys, indexes, transactions, normalization). Part 3 — 30 worked query problems on ONE consistent fictional e-commerce database: 10 Fundamentals, 10 Intermediate, 10 Advanced (window functions, running totals, RANK, dedupe, cohort retention, funnels, gaps, rolling averages, streaks, NTILE). Every problem: the business question, the SQL solution, why it works, the expected result shape, a common wrong answer with explanation, and a "try it yourself" variation. Part 4 — talk-through scripts: the 4-beat narration method, 3 fully narrated walkthroughs, phrases that score points. Part 5 — take-home assignment guide, 10 questions to ask your interviewer, the 24-hours-before checklist. Appendices: SQLite setup in 5 minutes, 14-day study schedule, SQL syntax cheat sheet (incl. SQLite → Postgres translation table, six query skeletons to memorize, window-function chooser, 10-minute pre-interview review), mock-interview scoring rubric + 20-minute mock script, 20 extra practice prompts, glossary, final self-assessment checklist.
• practice-database.sql — runnable SQLite script creating the exact 4-table database used in the book (44 customers, 22 products, 132 orders, 324 line items). Every one of the 30 solutions was executed against this database and independently re-verified.
• Practice-Workbook.docx (editable) — blank answer spaces for all 30 problems, 40-drill flashcard checklist, 14-day study tracker, mock-interview score log.
• README-license.txt — contents, free setup instructions, formats, license, disclaimer.

HOW IT WORKS

Download the ZIP → load practice-database.sql into the free DB Browser for SQLite (5 minutes; run a quick query first to confirm everything works) → drill Part 2 concepts out loud → work each Part 3 problem yourself BEFORE reading the solution → practice narrating with Part 4 → run two mock interviews with the rubric.

IDEAL CUSTOMER

A junior analyst or career changer with a SQL interview 2–4 weeks out who can put in a focused 14-day practice block and already writes basic SELECT queries.

WHO IT IS NOT FOR

• True SQL beginners: this is interview preparation, not a from-zero SQL course. You should already be able to write simple SELECT queries.
• Candidates interviewing primarily in a non-SQL language or in a dialect whose quirks dominate the interview (e.g., heavy Snowflake/BigQuery-specific testing) — dialect differences are noted, not exhaustively covered.
• Anyone who wants passivity: the value is in working the problems yourself; reading the solutions without doing the reps won't build interview fluency.

REQUIREMENTS & LIMITATIONS

• Prerequisites: basic SQL familiarity — you should already be able to write simple SELECT queries.
• Requires one free external tool: DB Browser for SQLite (5-minute setup guide included).
• PDF: any PDF reader. DOCX: Word, Google Docs, Apple Pages, LibreOffice.
• Limitations: interview preparation only. Not career counseling; no guarantee of interviews, job offers, or any salary. Solutions are standard SQL tested in SQLite; dialect differences (Postgres, MySQL, SQL Server) are noted where relevant — name your interview's dialect. All data is fictional.

FAQ

• I only know basic SQL — is this for me? Yes, if you can write simple SELECT queries. It's interview prep, not a from-zero course.
• Do the queries actually run? Yes — all 30 solutions were executed against the included database and independently verified. You run the same database yourself.
• Which SQL dialect? Standard SQL, tested in SQLite (free). Postgres/MySQL/SQL Server differences are noted where they matter.
• How long does preparation take? The book includes a 14-day schedule; compress it if your interview is sooner.
• What if I need help with the files? Message the seller through the Gumroad product page contact form.

DELIVERY & ACCESS

Instant download as a ZIP file (Query-Ready-SQL-Playbook-v1/) after purchase. Yours to keep; free updates to v1.x.

LICENSE

Licensed to you, the buyer, for personal use. You may not resell, share, redistribute, or republish these files.

SUPPORT & UPDATES

Questions or problems with the files: contact the seller via the Gumroad product page. All v1.x updates are free for life.

What's included

• Query Ready SQL Playbook (46-page PDF):
• Part 1 — how SQL interviews work (the 4 formats, what interviewers score, 2-week study plan, minute-by-minute anatomy of a 45-minute interview, reading EXPLAIN, what to do when stuck, red flags)
• Part 2 — 40 concept drills, each with a model answer and a "say it in the interview" line (execution order, JOINs, NULLs, COUNT pitfalls, GROUP BY/HAVING, DISTINCT, UNION, subqueries vs CTEs, window functions, CASE, dates, LIKE, keys, indexes, transactions, normalization)
• Part 3 — 30 worked query problems on ONE consistent fictional e-commerce database: 10 Fundamentals, 10 Intermediate, 10 Advanced (window functions, running totals, RANK, dedupe, cohort retention, funnels, gaps, rolling averages, streaks, NTILE). Every problem: the business question, the SQL solution, why it works, the expected result shape, a common wrong answer with explanation, and a "try it yourself" variation
• Part 4 — talk-through scripts: the 4-beat narration method, 3 fully narrated walkthroughs, phrases that score points
• Part 5 — take-home assignment guide, 10 questions to ask your interviewer, the 24-hours-before checklist
• Appendices: SQLite setup in 5 minutes, 14-day study schedule, SQL syntax cheat sheet (incl. SQLite → Postgres translation table, six query skeletons to memorize, window-function chooser, 10-minute pre-interview review), mock-interview scoring rubric + 20-minute mock script, 20 extra practice prompts, glossary, final self-assessment checklist
• Practice Database (SQL) — runnable SQLite script creating the exact 4-table database used in the book (44 customers, 22 products, 132 orders, 324 line items). Every one of the 30 solutions was executed against this database and independently re-verified.
• Practice Workbook (editable Word) — blank answer spaces for all 30 problems, 40-drill flashcard checklist, 14-day study tracker, mock-interview score log
• README & license file — contents, free setup instructions, formats, license, disclaimer

Key features

• Every solution executed and verified: 30/30 problem queries run cleanly against the included database; 10+ independently hand-verified against separate Python computations — you never study a solution that doesn't run, the genre's biggest failure mode.
• One consistent dataset — you learn the schema once and focus on the SQL, not on decoding a new table layout per problem.
• Standard SQL throughout, with Postgres/MySQL/SQL Server differences noted where they matter — you adapt to your interview's dialect instead of learning one dialect's quirks.
• Built for how interviews actually work: narration scripts, edge-case callouts, wrong-answer analysis — you rehearse the performance, not just the syntax.
• The cheat sheet packs the SQLite → Postgres translation table, six query skeletons, and the window-function chooser into a 10-minute pre-interview review — last-minute cramming that actually works.