Daily micro-tips for C#, SQL, performance, and scalable backend engineering.
🧹 Remove Using Statements Forever Every file starts with 10 using statements? Global usings define once for entire project. Implicit usings add common ones automatically. 📦 GlobalUsings.cs File // GlobalUsings.cs global using System; global using System.Collections.Generic; global using System.Linq; global using System.Threading.Tasks; global using Microsoft.Extensions.Logging; global using MyApp.Common; // Global using with alias global using […]
🎯 Replace if-else Chains with Switch Expressions Type checking, property matching, tuple patterns — switch expressions are more readable and less error-prone than long if-else. ❌ Old Way (Verbose) string GetDiscount(User user) { if (user == null) return “0%”; else if (user.Tier == “Gold”) return “20%”; else if (user.Tier == “Silver”) return “10%”; else if […]
🔍 Why Is My Query Slow? EXPLAIN ANALYZE shows exactly what the database does: table scans, index usage, join types, row estimates. The only real way to optimize. 📝 Basic Usage — PostgreSQL EXPLAIN ANALYZE SELECT * FROM users WHERE email = ‘alice@example.com’; — MySQL (no ANALYZE, use EXPLAIN only) EXPLAIN SELECT * FROM users […]
⏰ Which One Should You Use? Both run background tasks. IHostedService gives full control. BackgroundService handles stop logic. Choose wisely. 🔧 IHostedService (Full Control) public class MyService : IHostedService { private Timer _timer; public Task StartAsync(CancellationToken ct) { _timer = new Timer(DoWork, null, 0, 1000); return Task.CompletedTask; } public Task StopAsync(CancellationToken ct) { _timer?.Dispose(); return […]
🐛 Binary Search Through Git History Bug appeared sometime. Which commit? Git bisect does binary search through commits. Find the culprit in O(log n) steps. 🔧 Basic Bisect Workflow # Start bisect git bisect start # Mark current commit as bad (bug exists) git bisect bad # Mark a known good commit (no bug) git […]
📡 One-Way Real-Time from Server to Client Need server push but WebSockets are overkill? SSE sends updates from server to browser. Stock tickers, notifications, live feeds. 📝 Server-Side (Node.js Example) app.get(‘/events’, (req, res) => { res.writeHead(200, { ‘Content-Type’: ‘text/event-stream’, ‘Cache-Control’: ‘no-cache’, ‘Connection’: ‘keep-alive’ }); // Send data every 5 seconds const interval = setInterval(() => […]
?? vs || — The Important Difference `||` treats 0, ”, false as falsy. `??` only checks `null` and `undefined`. Use ?? for default values. ❌ Logical OR (||) Trap const count = userInput || 10; // If userInput = 0 → count = 10 (WRONG!) const name = userName || ‘Guest’; // If userName […]
📂 Native Accordion, Zero JavaScript <details> and <summary> create expandable/collapsible sections. Works everywhere, no JS, accessible by default. 📝 Basic Usage <details> <summary>Click to expand</summary> <p>This content is hidden until you click the summary.</p> <ul> <li>Can contain any HTML</li> <li>Multiple lines</li> <li>Images, lists, anything!</li> </ul> </details> <details open> <summary>Expanded by default</summary> <p>Add the ‘open’ attribute […]
🎨 One Variable Change, Whole Site Updates Sass variables compile once. CSS variables update at runtime. Dark mode, dynamic theming, component libraries — finally possible. 📦 Defining and Using Variables /* Define on :root (global) */ :root { –primary-color: #3498db; –secondary-color: #2ecc71; –spacing-unit: 8px; –border-radius: 4px; –font-size-base: 16px; } /* Use variables */ .button { […]
📋 Copy Once, Paste Many Times Default clipboard only holds one item. Clipboard history saves everything you copy. Access items from hours ago. 🔧 Enable Clipboard History Settings → System → Clipboard Or press Win + V → Turn on ⌨️ Shortcuts Win + V → Open clipboard history Win + V, then click → […]
🗣️ “Show me users who ordered in last 30 days” → SQL Don’t remember JOIN syntax? AI generates SQL from natural language. Perfect for non-developers or when you’re stuck. 📝 The SQL Generation Prompt Given this database schema: Table: users – id (INT, PRIMARY KEY) – name (VARCHAR) – email (VARCHAR) – created_at (DATETIME) Table: […]
🎭 One Compose File, Multiple Environments Don’t duplicate docker-compose.yml. Profiles start only the services you need for each environment. 📦 docker-compose.yml with Profiles version: ‘3.8’ services: app: image: myapp:latest ports: – “8080:8080” profiles: [“prod”, “dev”] # Always start postgres: image: postgres:15 environment: POSTGRES_PASSWORD: secret profiles: [“prod”, “dev”] redis: image: redis:alpine profiles: [“prod”] # Only production […]
❤️ Is Your App Alive AND Ready? Liveness = restart if dead. Readiness = don’t send traffic until ready. Use both for zero-downtime deployments. 💓 Liveness Probe livenessProbe: httpGet: path: /healthz port: 8080 initialDelaySeconds: 30 periodSeconds: 10 If fails → Kubernetes restarts container. ✅ Readiness Probe readinessProbe: httpGet: path: /ready port: 8080 initialDelaySeconds: 5 periodSeconds: […]
⏰ WP-Cron Runs on Page Views — That’s Bad WP-Cron triggers on visitor traffic. No visitors? Tasks never run. Replace with system cron for reliable scheduling. 🔧 Disable WP-Cron # Add to wp-config.php define(‘DISABLE_WP_CRON’, true); 📦 Set Up System Cron # Every 5 minutes */5 * * * * wget -q -O – https://yoursite.com/wp-cron.php?doing_wp_cron >/dev/null […]
🎨 Multiply, Screen, Overlay — What’s the Difference? Blending modes change how layers interact. Multiply, Screen, Overlay, Soft Light — master these and unlock professional effects. 🌑 Multiply Darkens image. White becomes transparent. Great for shadows, adding density. Use for: Drop shadows, line art overlay ☀️ Screen Lightens image. Black becomes transparent. Perfect for highlights, […]
🤖 AI Knows What You’re About to Type IntelliCode analyzes your code patterns and suggests completions ranked by AI. GitHub Copilot Lite, built into VS. ✨ What IntelliCode Does Starred completions → Most likely API calls at top of list Style inference → Learns your naming conventions (camelCase, PascalCase) Code formatting → Applies team style […]