SQLPrep vs Data_Engineering

SQLPrep helps data analyst candidates practice SQL in the minutes between real responsibilities. Work through daily multiple-choice drills, then write real queries against bundled SQLite databases. Every exercise runs locally on your device, so practice is fast, private, and available without an account or internet connection. What you can practice: - SELECT, WHERE, ORDER BY, and LIMIT - Aggregate functions, GROUP BY, and HAVING - JOIN basics and advanced JOIN patterns - Subqueries, CASE, and NULL handling - Window functions - Mixed interview-style SQL problems SQLPrep is built for focused interview preparation. It avoids streak pressure, mascots, ads, subscriptions, and account setup. Instead, you get a local practice log, chapter accuracy percentages, structured query diagnostics, and a clean dark interface designed for serious study. Free practice includes Chapter 1, the first 5 SQLite exercises, and a daily quiz allowance. Unlock Full Practice Library is a one-time purchase that unlocks the full local bank: 200 interview questions and 60 SQLite exercises. No subscription. Download SQLPrep and run your first real query in under a minute — no account, no internet required.

Become a data engineer—starting exactly where you are. Data_Engineering is a complete interactive learning environment for iPhone, iPad, and Mac. Begin with basic arithmetic, first Python, files, SQL, and databases. Progress into production pipelines, data modeling, warehouses, Airflow, dbt, Spark, Kafka, cloud platforms, quality, governance, observability, and principal-level architecture. LEARN BY DOING • 40 structured courses from beginner to advanced • 400 substantive interactive lessons • 140 editable, syntax-highlighted code labs • 100 quizzes with validation and explanations • 80 architecture decisions based on real trade-offs • 80 guided concept exercises • Progressive hints that help without giving the answer away BUILD A PORTFOLIO Complete 40 practical data engineering projects: 12 Beginner, 14 Intermediate, and 14 Advanced. Every build includes an editable SQL, Python, YAML, or architecture workspace, four milestones, local checks, and a concrete outcome you can explain in an interview. YOUR PRIVATE DATA ENGINEERING TUTOR Ask a question from any lesson or project. Tutor Core can begin with basic arithmetic, define every new term, and work toward deep production trade-offs. Offline Core is included and never sends questions anywhere. Compatible devices can add private Apple on-device generation. External providers are always optional. WATCH YOUR DATA PLATFORM TAKE SHAPE Every completed lesson, course, and project milestone advances a living data-platform construction scene—from its first frame through ingestion, transformations, integration, and operational control planes. DESIGNED FOR SERIOUS PROGRESS Earn XP, build streaks, bookmark material, track role readiness, choose daily goals, switch between light and dark interfaces, and move naturally among iPhone, iPad, and Mac. SUBSCRIPTION Data_Engineering Pro includes a 14-day free introductory trial for eligible new subscribers, then renews monthly at the price shown in the app. Payment is charged to your Apple Account after confirmation. The subscription automatically renews unless cancelled at least 24 hours before the end of the current period. Manage or cancel in Apple Account subscription settings. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://github.com/lukekevinmclaughlin-oss/Data_Engineering/blob/main/PRIVACY.md