10 Costly Database Performance Mistakes (and How to Fix Them)
Andrew Atkinson • Philadelphia, PA • Talk

Date: July 08, 2025
Published: not published
Announced: unknown

After working with countless Rails and Postgres applications as a consultant and backend engineer, I’ve seen firsthand how database mistakes can cause big costs and headaches. Poor data types, inefficient queries, and flawed schema designs slow down operations, and result in excessive costs through over-provisioned servers, downtime, lost users, and engineering hours spent restructuring features.

How do we prevent these pitfalls? Awareness is the first step. And if your database is already serving tons of woefully inefficient queries, where should you focus for the biggest wins?

In this talk, we'll break down 10 real-world Rails database mistakes, including how they happened, the impact they had, and most importantly, how to fix them. Topics include query design, indexing, schema optimization, and how the CPU, memory, and IOPS resources tie into Active Record SQL performance.

Expect practical takeaways, real examples, and solutions you can apply immediately. Slides and blog posts will be available at GitHub.

RailsConf 2025