Database indexes are the difference between a query that completes in milliseconds and one that brings your application to its knees. After optimizing databases for over a decade—from small startups to systems handling billions of queries daily—I’ve learned that understanding indexes deeply is essential for building performant applications. A well-placed index can transform a 30-second query into one that completes in 10 milliseconds. This guide explains how indexes work internally and how to use them effectively in production.
SQL injection (SQLi) has topped the OWASP Top 10 vulnerability list for over a decade. After spending years conducting security audits and penetration tests, I’ve witnessed firsthand how this seemingly simple vulnerability can completely compromise web applications. Despite being well-understood, SQL injection continues to plague production systems—I discovered critical SQLi vulnerabilities in enterprise applications as recently as 2024. This guide explains how SQL injection works, how attackers exploit it, and most importantly, how to prevent it.
PostgreSQL is one of the most powerful open-source relational database management systems available today. However, achieving optimal performance requires understanding its internals and applying the right tuning strategies. This comprehensive guide explores essential PostgreSQL performance tuning techniques that can dramatically improve your database’s efficiency.
Before diving into optimization, it’s crucial to understand PostgreSQL’s architecture. PostgreSQL uses a multi-process architecture where each client connection spawns a separate backend process. This design provides excellent isolation but requires careful resource management.