SQL Reporting: Grouping, Counts & Report Grain
Reason about report rows, aggregate calculations and deterministic query output.
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JavaScript: Missing Values & Safe Defaults
Distinguish missing data from valid empty values and choose precise defaults.
JavaScript: Destructuring, Rest & Spread
Reason about extraction, defaults, shallow copies, and object merge order.
JavaScript: Sorting & Comparator Decisions
Predict ordering, avoid unwanted mutations, and define reliable tie breakers.
CSS: Container Query Components
Make reusable components respond to their available space.
CSS: Stacking Contexts & Overlays
Explain why overlays hide behind other elements and fix the right layer.
CSS Grid: Tracks, Placement & Sizing
Work through flexible tracks, implicit rows, and content-driven overflow.
Accessibility: Image Alternatives in Context
Choose meaningful text alternatives for icons, charts, links, and decorative images.
Accessibility: Status Messages & Live Regions
Announce interface updates clearly without overwhelming or moving users.
HTTP: CORS & Browser Request Boundaries
Diagnose cross-origin reads, preflights, credentials, and server policies.
HTTP: Conditional Writes & Edit Conflicts
Prevent lost updates and recover from stale resource versions.
Git: Undo, Restore & Recovery
Choose the right operation for shared commits, staged changes, and recovery.
SQL: Joins, NULL & Aggregation
Predict result rows and counts before trusting a report.
Google Apps Script Fundamentals & Services
Test the runtime, authorization model, built-in services, logging, web apps, and core patterns used in Apps Script projects.
JavaScript Arrays, Objects & Data Transformations
Challenge your understanding of immutable updates, array methods, references, destructuring, Maps, Sets, and reliable data pipelines.
JavaScript Prototypes, Classes & Modules
Reason through prototype lookup, class behavior, private fields, inheritance, module bindings, imports, and reusable code boundaries.
JavaScript Testing, Debugging & Error Handling
Test assertions, async tests, mocks, stack traces, error design, debugging tools, and strategies for trustworthy JavaScript.
JavaScript Performance, Memory & the Browser
Reason about measurement, rendering work, event handlers, memory retention, workers, data structures, and scalable frontend performance.
Apps Script for Google Sheets Automation
Work through challenging questions about ranges, values, batching, formulas, filters, and reliable spreadsheet automation.
Apps Script Triggers, APIs & Reliable Automation
Test trigger identities, event objects, locks, caching, external requests, advanced services, and production automation design.
CSS Layout: Grid, Flexbox & Sizing
Reason through intrinsic sizing, Grid tracks, Flexbox alignment, overflow, containing blocks, and robust layout choices.
CSS Cascade, Specificity & Maintainable Styles
Master cascade layers, specificity, inheritance, custom properties, selectors, and architecture decisions that keep CSS predictable.
Responsive, Accessible & Modern CSS
Test container queries, logical properties, media preferences, fluid sizing, focus styles, and resilient responsive design.
Game Design: Mechanics, Goals & Player Choices
Identify useful mechanics, meaningful decisions and clear goals when designing a small game.