SQL Quiz Drills

■ No engine required. Run SELECT in your head. SQLのエ is an iPhone app for practicing SQL in spare moments. Browser-based SQL playgrounds require sitting down at a PC; this app trades the engine for high-density questions, building real SQL skill through quick quizzes, repetition, and clear progress. ■ Who it's for - New engineers who want SQL at their fingertips - Analysts who need to read the SQL behind BI tools - Anyone preparing for database/IT certification exams - People who write SQL "by feel" and want to truly understand it ■ SQL-focused question formats - Four-choice (fundamentals): quickly check syntax and terms - Result-table prediction: guess the output from a table + query (our signature format) - Fill-in-the-blank: memorize keywords - True/False: check knowledge with rhythm ■ Learning modes - Chapter training: basics through SELECT, WHERE, sorting, aggregates, GROUP BY, JOIN, subqueries, set operations - Test: no explanations, just a score - Oni (hard) training: 10 seconds per question, combos for streaks - Daily 5: a fresh hand-picked set each day ■ Built to keep you going - Streak (consecutive study days) - Total queries solved and overall accuracy - Per-chapter accuracy heatmap - Achievement badges ■ Readable by design - Dark theme with SQL syntax highlighting and monospaced font - Clear result-table display ■ Privacy-first - No account, no ads - Works fully offline - Learning data stays on your device (never sent out) "10 questions a day. Run SELECT in your head." Make SQL a habit, starting today. Note: The app does not execute real SQL. To try queries for real, use the external links (e.g., DB Fiddle) in Settings.