SQL Practice - Learn SQL

Halim Box Dev

In-app purchases

About this app

Learn SQL by actually writing it. Every exercise runs on a real SQLite database inside your phone, so you type real queries, see real result tables and get instant feedback, with no internet connection needed.

A REAL SQL ENGINE IN YOUR POCKET
• Real SQLite runs on your device: SELECT, JOIN, GROUP BY, subqueries, CTEs, window functions, INSERT, UPDATE and DELETE
• Four practice databases (company, shop, movies, school) to explore freely
• Code editor with keyword and table/column suggestion chips
• Your result is compared with the expected answer row by row, so you see exactly what is different
• Plain-English explanations for common errors such as "no such column" or "ambiguous column name"
• Schema drawer and table diagram so you always know which columns exist

60 LESSONS IN 10 UNITS
Short concept cards with worked examples, followed by hands-on exercises:
• Selecting and filtering data (WHERE, IN, BETWEEN, LIKE, NULL)
• Sorting and pagination (ORDER BY, LIMIT, OFFSET)
• Aggregates and grouping (COUNT, SUM, AVG, GROUP BY, HAVING)
• Joins of every kind, self joins and multi-table queries
• Subqueries, CTEs and CASE expressions
• Window functions (ROW_NUMBER, RANK, running totals)
• Changing data and creating tables

150 CHALLENGES + A DAILY PUZZLE
• 50 easy, 50 medium and 50 hard challenges
• A new daily challenge every day
• Hard challenges unlock with a short optional video or with Pro

SQL INTERVIEW PREP
• 120 interview questions with clear answers
• Timed mock interview to practise answering under pressure
• Bookmark the questions you want to review again

20 PORTFOLIO PROJECTS
Multi-step projects on realistic business data, such as revenue analysis and salary benchmarking, unlocked after Unit 5 or with Pro.

BUILD A DAILY HABIT
• Pick a daily goal of lessons or challenges
• Streaks with streak freezes so one busy day does not reset your progress
• Optional daily reminder at the time you choose

PRIVATE AND OFFLINE
Your queries and progress stay on your device. No account needed.

Free with ads. A one-time Pro purchase removes ads and unlocks all hard challenges and projects. No subscription.