Welcome to Özkan Pakdil’s Blog

PostgreSQL 🐘 is a robust database, but its MVCC (Multi-Version Concurrency Control) design can sometimes lead to a subtle issue: table and index bloat. If left unchecked, bloat wastes storage, increases I/O, and can slow queries down. In this post, I’ll walk through: What bloat is and why it happens Different ways to measure it How to keep an eye on it without killing your database A few habits to reduce or fix it What is bloat? 🧹 Table bloat: Every update creates a new row version, and the old one becomes dead. Those dead tuples sit there until vacuum cleans them. Index bloat: Even when dead tuples are gone from the table, their index entries may stick around until an index vacuum or reindex. Why care? ...

When implementing secure PostgreSQL connections, certificate creation forms the foundation of your PKI infrastructure. Whether you’re setting up a development environment or deploying enterprise-grade systems, understanding proper certificate creation practices is crucial. This guide explores certificate creation from the simple OpenSSL approach to enterprise-grade practices employed by major financial institutions like Credit Suisse/UBS and media companies like BBC. Related Reading: For implementing DN-based certificate authentication in PostgreSQL, see our DN Authentication guide. ...

Today, I’m diving into Distinguished Name (DN) authentication—a powerful feature that enables certificate-based authentication when the Common Name (CN) in your client certificate doesn’t match your PostgreSQL username. This approach is essential in enterprise environments where certificate naming conventions don’t align with database user naming requirements. Version Compatibility: The clientname=DN feature was introduced in PostgreSQL 14. If you’re using PostgreSQL 13 or earlier versions, this DN authentication method will not work and you’ll need to use traditional CN-based certificate authentication instead. ...

Mutual TLS (mTLS) for PostgreSQL provides strong, passwordless authentication and encryption. The most common cause of failed secure connections in real deployments is incorrect Subject Alternative Name (SAN) handling and trust configuration on the client side. This post explains how to set up SANs correctly, how hostname verification really works, and how to align PostgreSQL with enterprise PKI practices—using this repository’s cluster as a concrete example. Why SAN Matters More Than CN Modern TLS stacks validate the server’s identity against the SAN extension on the server certificate—not the Common Name (CN). When a PostgreSQL client connects to a host name (or IP), it will check: ...

🚀 The Pagination Pitfall: A React + Spring Boot Cautionary Tale The Setup: “It’ll Be Fine…” A few years ago, I was working on a dashboard application with a React frontend and a Spring Boot backend. The task seemed simple: display a list of users with pagination. One of the newer devs suggested: “Let’s just fetch everything once and paginate on the client side — it’ll be faster for the user.” ...