What are N+1 query issues in Rails?

What are N+1 query issues in Rails?

N+1 query issues occur when an application makes one query to retrieve a list of records and then makes additional queries for each record to fetch associated data, leading to performance problems.

How can I identify N+1 query issues in my Rails app?

You can use tools like Bullet or the Rails logger to identify N+1 queries. They will alert you when your app makes excessive queries.

What are some ways to fix N+1 query issues?

You can fix N+1 issues by using eager loading with the includes method, which loads associated records in a single query.

Can you give me an example of eager loading?

Sure! Instead of Post.all.each { |post| post.comments }, use Post.includes(:comments).each { |post| post.comments } to load comments in one query.