Performance & Query Debugging

Diagnosing slow ActiveRecord queries, N+1 issues, and performance mismatches between SQL and Rails, using real production examples.

ActiveRecord query patterns that prevent PostgreSQL from using database indexes with solutions for functional indexes and composite keys

Database Indexes Existed. ActiveRecord Ignored Them.

Fix ActiveRecord queries that bypass indexes. Learn 6 patterns that break index usage and how to rewrite them. Real production benchmarks from 200K+ row tables.

March 25, 2026 10 min read

Rails WHERE Clause in ActiveRecord: Conditions, Multiple Clauses, and OR Logic

Master Rails WHERE clause with multiple conditions, OR logic, and SQL strings. Learn WHERE vs HAVING and how to verify generated SQL with real examples.

January 28, 2026 5 min read

Ruby 4.0.0 Is Out: What Rails & ActiveRecord Devs Actually Need to Know

Ruby 4.0.0 is released (Dec 25, 2025). For Rails apps, the real risks are stdlib gem changes (CGI), Net::HTTP behavior shifts, and Bundler 4. Here’s what breaks

December 27, 2025 6 min read

Rails 8.2 Preview: What Production Apps Actually Gain in 2026

A production-focused preview of Rails 8.2 explaining real-world impact on caching, TypeScript integration, Turbo behavior, and upgrade risks.

November 11, 2025 3 min read