Cirquanta vs Learn SQL

Make digital logic visible. Cirquanta is a native circuit simulator for iPhone and iPad. Build clear schematics, connect components directly on the canvas, and watch every logical signal react in real time. Whether you are learning Boolean logic, teaching digital electronics, or sketching a design before HDL or firmware, Cirquanta gives you a focused workspace that works offline. DESIGN ON THE CANVAS • Choose and place 60+ components from an organized library • Move, wire, rotate, duplicate, and configure elements with undo and redo • Select several parts at once, then move, duplicate, copy, or cut the whole sub-circuit and paste it into any circuit, wiring included • Organize larger designs with buses, zones, sticky notes, zoom, full screen, and curved or right-angle wires SIMULATE IN REAL TIME • Toggle switches and inputs directly on your circuit • Run, pause, advance step by step, or reset the simulation • Follow color-coded signals with deterministic four-state logic: 0, 1, unknown X, and high-impedance Z LEARN WITH CHALLENGES • Work through a 30-level campaign, from a single wire to a state machine • Follow a clear objective, with optional hints and step-by-step guidance • Earn up to three stars per challenge, graded on correctness and efficiency • Play the first six challenges free; unlock the whole campaign with Pro GO FROM GATES TO SEQUENTIAL LOGIC Start with AND, OR, NOT, NAND, NOR, XOR, and XNOR gates. Then explore multiplexers, demultiplexers, decoders, encoders, adders, latches, D/JK/T flip-flops, registers, counters, buses, clocks, LEDs, probes, and displays. PRIVATE BY DESIGN • No account and no sign-up: just open the app and start building • Works fully offline; your circuits are saved locally on the device • No ads, and your data is never sold; your designs stay yours • Optional private iCloud sync between your own devices with the same Apple Account (iCloud is never required) KEEP CONTROL OF YOUR PROJECTS • Start from a blank canvas or a built-in example • Search, sort, favorite, and archive your circuits • Export a portable backup to save or share your work Free to start with room for 3 circuits and up to 24 components each, plus six free challenges. Unlock Cirquanta Pro once for unlimited circuits and components and the full challenge campaign, with no subscription. Cirquanta is made for students, teachers, makers, and developers who want to understand or prototype digital systems. It simulates digital logic only; it is not an analog or SPICE simulator.

Open the case file. The evidence is in the database. Learn SQL for free through 100 authored leads and 10 complete investigations. Read the brief, inspect the schema, write a real query, and use the returned rows to prove what happened. Each lead gives you a question and a working dataset. Run your SQL, study the result, revise your approach, then verify the finding when the evidence fits. Every investigation is authored, so the clues, datasets, and conclusions belong to a complete case. WORK 100 AUTHORED LEADS Ten investigations take you from the foundations to advanced analysis: • SELECT, WHERE, ORDER BY, and LIMIT • COUNT, SUM, AVG, GROUP BY, and HAVING • INNER JOIN and LEFT JOIN • Subqueries and CASE expressions • Window functions and common table expressions BUILD PRACTICAL SQL JUDGEMENT • Turn a case objective into a query • Explore tables and relationships through the schema • Read returned rows instead of guessing from syntax • Use clear feedback to correct a failed investigation • Reopen filed leads and improve your solution START WHERE YOUR SKILLS FIT New to SQL? Begin with Case 001 and learn the query desk step by step. Already comfortable with the basics? Choose a later investigation and meet a harder set of evidence. Archie, your SQL Case Guide, can offer a focused hint when you are stuck. Academy field guides explain the underlying concepts, while the Skill Map shows how each investigation builds your SQL toolkit. THE CURRICULUM STAYS FREE All 100 authored leads and the complete SQL learning route are free. There is no subscription. Start without an account, and keep your learning progress and settings on your device. Analytics can be disabled in Settings. Query verification, Archie guidance, verification links, and purchase restoration require an internet connection. An optional one-time Supporter purchase helps fund future investigations. It never limits the curriculum. Your first case is waiting.