Fix N+1 Queries Without Eager Loading Using SQL Subquery

Learn how to address the N+1 query problem in Rails without resorting to eager loading. By leveraging SQL subqueries, you can fetch specific associated records directly within your main query, reducing memory consumption and improving performance. The post walks through a real-world example of fetching a member's latest activity timestamp efficiently, discussing various approaches and their trade-offs before demonstrating the optimal SQL subquery solution.