Daily micro-tips for C#, SQL, performance, and scalable backend engineering.
Manual null checks are verbose. C# 11 has built-in helper for cleaner validation. Old Way: public void ProcessUser(User user, string name, ILogger logger) { if (user == null) throw new ArgumentNullException(nameof(user)); if (name == null) throw new ArgumentNullException(nameof(name)); if (logger == null) throw new ArgumentNullException(nameof(logger)); // Actual logic… } New Way (C# 11): public void […]
Variables you’ll never use clutter code. Discards (_) explicitly mark them as unused. Tuple Deconstruction: // Don’t need middle value var (first, _, last) = (“John”, “middle”, “Doe”); // Don’t need first two var (_, _, important) = GetThreeValues(); Out Parameters: // Only care if it parses, not the value if (int.TryParse(input, out _)) { […]
Returning multiple values via out parameters is messy. Tuples with deconstruction are clean. Old Way (out parameters): public bool TryParse(string input, out int result, out string error) { // Ugly signature, can’t use in expressions } // Usage if (TryParse(input, out int result, out string error)) { // … } Tuple Return: public (bool success, […]
Helper classes polluting your namespace? File-scoped types are only visible in their file. Problem: // HelperClass visible everywhere in project public class ProductService { // … } public class HelperClass // Only used by ProductService { // But visible to entire project! } Solution – File-Scoped Types: // ProductService.cs public class ProductService { private readonly […]
Displaying row data as columns manually requires complex CASE statements. PIVOT does it automatically. Source Data: Month Product Sales January Widget 100 January Gadget 150 February Widget 120 February Gadget 180 PIVOT Query: SELECT * FROM ( SELECT Month, Product, Sales FROM SalesData ) AS SourceTable PIVOT ( SUM(Sales) FOR Product IN ([Widget], [Gadget]) ) […]
After MERGE, don’t know what was inserted vs updated? OUTPUT clause captures the changes. MERGE with OUTPUT: MERGE INTO Products AS target USING @NewProducts AS source ON target.ProductId = source.ProductId WHEN MATCHED THEN UPDATE SET Price = source.Price WHEN NOT MATCHED THEN INSERT (ProductId, Name, Price) VALUES (source.ProductId, source.Name, source.Price) OUTPUT $action AS Action, INSERTED.ProductId, […]
Network failures happen. Polly adds retry, circuit breaker, and timeout policies automatically. Install: dotnet add package Polly dotnet add package Microsoft.Extensions.Http.Polly Add to HttpClient: // Program.cs builder.Services.AddHttpClient(“MyAPI”, client => { client.BaseAddress = new Uri(“https://api.example.com”); }) .AddTransientHttpErrorPolicy(policy => policy.WaitAndRetryAsync(3, attempt => TimeSpan.FromSeconds(Math.Pow(2, attempt))) ) .AddTransientHttpErrorPolicy(policy => policy.CircuitBreakerAsync(5, TimeSpan.FromMinutes(1)) ); Usage: public class MyService { private readonly […]
Entity Framework too heavy for simple queries? Dapper is micro-ORM with near-raw SQL performance. Install: dotnet add package Dapper Basic Usage: using Dapper; using System.Data.SqlClient; var connection = new SqlConnection(connectionString); // Query (returns list) var users = connection.Query( “SELECT * FROM Users WHERE Age > @MinAge”, new { MinAge = 18 } ).ToList(); // Single […]
Cloning huge repo when you only need one folder wastes time and disk. Sparse checkout downloads only what you need. Clone with Sparse Checkout: # Clone repository (no files yet) git clone –no-checkout https://github.com/user/repo.git cd repo # Enable sparse checkout git sparse-checkout init –cone # Specify folders you want git sparse-checkout set frontend/src backend/api # […]
git checkout does too many things (switch branches, restore files, create branches). Git 2.23+ splits it into clear commands. Old Confusing Way: # Switch branch git checkout main # Create and switch to new branch git checkout -b feature # Restore file git checkout — file.txt # All same command! Confusing! New Clear Commands: # […]
Regular fetch() in beforeunload is unreliable – browser may cancel it. Beacon API guarantees delivery. Problem with fetch(): window.addEventListener(‘beforeunload’, () => { fetch(‘/api/analytics’, { method: ‘POST’, body: JSON.stringify(data) }); // Browser often cancels this! }); Solution – Beacon API: window.addEventListener(‘beforeunload’, () => { navigator.sendBeacon(‘/api/analytics’, JSON.stringify({ timeSpent: Date.now() – pageLoadTime, scrollDepth: getScrollDepth(), clickData: clickTracker })); // […]
Frameworks like Vue use Proxy for reactivity. You can too – update UI automatically when data changes. Basic Reactive Object: const data = { count: 0, name: ‘John’ }; const reactive = new Proxy(data, { set(target, property, value) { target[property] = value; // Update UI automatically document.getElementById(property).textContent = value; console.log(`${property} changed to ${value}`); return true; […]
Creating progress bars with divs and CSS is complex. HTML5 meter shows value ranges natively. Basic Usage: <meter min=”0″ max=”100″ value=”75″>75%</meter> With Optimal Ranges: <meter min=”0″ max=”100″ low=”25″ high=”75″ optimum=”50″ value=”80″> 80% (High) </meter> <!– Browser colors bar automatically: 0-25: Red (low) 25-75: Yellow (medium) 75-100: Green (high) –> Use Cases: – Disk usage – […]
:focus shows outline on mouse clicks (annoying). :focus-visible shows only for keyboard navigation. Old Way (:focus): button:focus { outline: 2px solid blue; } /* Problem: Shows outline when clicked with mouse Users disable it: outline: none; (BAD for accessibility!) */ Better Way (:focus-visible): button:focus { outline: none; /* Remove default */ } button:focus-visible { outline: […]
Don’t know your battery’s real health? Windows generates detailed battery report from command line. Generate Report: # Run as Administrator powercfg /batteryreport # Output: C:\Windows\System32\battery-report.html Report Shows: – Design capacity vs current capacity – Battery health percentage – Charge/discharge history – Battery usage over time – Battery life estimates Example: Design Capacity: 50,000 mWh Full […]
Switching between multiple computers is annoying. Mouse Without Borders shares one keyboard/mouse across up to 4 PCs. Install: Download “Mouse Without Borders” from Microsoft Setup: 1. Install on all PCs 2. On first PC: Get security code 3. On other PCs: Enter that code 4. Done! Mouse moves seamlessly between screens Features: – Drag mouse […]
Manual security reviews miss issues. AI scans code for common vulnerabilities comprehensively. The Prompt: Review this code for security vulnerabilities: [Paste code] Check for: 1. SQL Injection 2. XSS (Cross-Site Scripting) 3. CSRF vulnerabilities 4. Authentication issues 5. Authorization flaws 6. Input validation problems 7. Sensitive data exposure 8. Insecure dependencies 9. API security issues […]
Designing database schema takes hours. AI creates normalized schema with relationships instantly. The Prompt: Design database schema for: [Describe your application] Requirements: 1. Normalized (3NF minimum) 2. Include primary keys, foreign keys 3. Add indexes for common queries 4. Specify data types (be specific) 5. Add constraints (NOT NULL, UNIQUE, etc.) 6. Show relationships (1:1, […]
Writing user stories from requirements is tedious. AI converts them automatically in proper format. The Prompt: Convert these requirements to user stories: [Paste requirements document] Format each as: – As a [role] – I want [feature] – So that [benefit] Also include: – Acceptance criteria (Given/When/Then) – Story points estimate (1-13 scale) – Priority (High/Medium/Low) […]
Confusing ARG and ENV causes build issues. Know when to use each. ARG – Build-Time Only: FROM node:18 ARG NODE_ENV=production ARG API_URL=https://api.example.com RUN echo “Building for ${NODE_ENV}” RUN npm install –${NODE_ENV} # ARG values NOT available at runtime! Build with ARG: docker build –build-arg NODE_ENV=development -t myapp . ENV – Runtime Variables: FROM node:18 ENV […]
Storing passwords in ConfigMaps exposes them in plain text. Secrets encode data and have better access control. Create Secret: kubectl create secret generic db-secret \ –from-literal=username=admin \ –from-literal=password=secretpass123 Use in Pod: apiVersion: v1 kind: Pod metadata: name: myapp spec: containers: – name: app image: myapp:1.0 env: – name: DB_USER valueFrom: secretKeyRef: name: db-secret key: username […]
Running heavy tasks on page load slows site. Action Scheduler queues tasks to run in background. Install: Built into WooCommerce, or install standalone “Action Scheduler” plugin Schedule Task: // Schedule single action as_schedule_single_action( time() + 3600, // 1 hour from now ‘my_custom_hook’, array(‘user_id’ => 123) // Arguments ); // Schedule recurring action (daily) as_schedule_recurring_action( time(), […]
Database queries on every page load are slow. Redis caches objects in memory for instant access. Install Redis Plugin: “Redis Object Cache” by Till Krüss Setup Redis Server: # Ubuntu/Debian sudo apt install redis-server sudo systemctl start redis sudo systemctl enable redis Configure WordPress (wp-config.php): define(‘WP_REDIS_HOST’, ‘127.0.0.1’); define(‘WP_REDIS_PORT’, 6379); define(‘WP_CACHE’, true); Enable in Plugin: Settings […]
Regular Content-Aware Fill sometimes creates visible seams. Color Adaptation setting makes fills blend perfectly. Steps: 1. Select area to fill 2. Edit → Content-Aware Fill (not just Fill) 3. In sidebar: Check “Color Adaptation” 4. Adjust sampling brush to exclude unwanted areas 5. Click OK What Color Adaptation Does: Blends colors from surrounding area seamlessly […]
Editing objects in perspective manually looks distorted. Vanishing Point maintains correct perspective automatically. Access: Filter → Vanishing Point How to Use: 1. Create Plane tool: Click 4 corners of a perspective surface (wall, floor, etc.) 2. Clone/Stamp/Paint within defined plane 3. Edits automatically match perspective! Use Cases: – Remove text from building wall – Clone […]
Constantly opening files to check definitions? Peek Definition shows code inline without switching files. Use Peek: Right-click symbol → Peek Definition (or Alt+F12) Features: – Shows definition in popup window – Edit code directly in peek window – Navigate to related definitions – Multiple peeks can be open simultaneously Keyboard Navigation: – Alt+F12: Peek Definition […]