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activerecord_n_plus_one_benchmark

🛠️ Benchmark ActiveRecord to Detect N+1 Queries​

Compare plain queries vs. eager‑loaded queries to avoid N+1 issues. Wrap both in a benchmark block to quantify the gain from using includes.

require 'benchmark'

Benchmark.bm(15) do |x|
  x.report('without includes:') do
    100.times { Post.all.each { |p| p.comments.size } }
  end

  x.report('with includes:   ') do
    100.times { Post.includes(:comments).each { |p| p.comments.size } }
  end
end

This prints a side‑by‑side comparison. If with includes is significantly faster, eager loading is saving you database round trips.