When interviewing for backend or data roles, you’ll often see the classic problem: “Find the second highest salary from the Employee table. If there is no secon...
Introduction If you develop systems using Java with JPA, you have probably faced the need to execute queries that return only a subset of attributes from a giv...
The Problem: The Full Table Scan Imagine a library with 1 million books. If you want to find The Great Gatsby and the books aren't organized, you have to look...
Scaling PostgreSQL for a High‑Traffic Application Over the past two years we’ve reduced query times from > 15 seconds to = '2024-01-01' ORDER BY o.created_at D...
The Execution Layer Isn’t “Just Execution” Architectural diagrams often split a query engine into neat boxes: - SQL parsing - Optimization - Plan generation -...
Hello, I'm Maneshwar. I'm working on FreeDevTools onlinehttps://hexmos.com/freedevtools, currently building one place for all dev tools, cheat codes, and TLDRs...
Background When I inherited a Laravel application that was struggling with performance, the user dashboards were loading related data such as orders, customers...
Article URL: https://emschwartz.me/short-circuiting-correlated-subqueries-in-sqlite/ Comments URL: https://news.ycombinator.com/item?id=46300776 Points: 6 Comme...
How I solved the N+1 query problem using JSON aggregation instead of traditional eager loading Last month, I was debugging a slow admin dashboard. The page load...
1. The Nightmare: The Full Table Scan Imagine walking into a library with 100,000 books and looking for a specific title. If the books are just piled in the mi...
After years of managing database‑driven applications, I've learned that query optimization can make or break your application's performance. Here are five pract...
