Counting the number of queries performed

Question

I\'d like to test that a certain piece of code performs as few SQL queries as possible.

ActiveRecord::TestCase seems to have its own assert_querie

Answer 1

Here's another formulation of Ryan's and Yuriy's solution that's just a function you add to your test_helper.rb:

def count_queries &block
  count = 0

  counter_f = ->(name, started, finished, unique_id, payload) {
    unless payload[:name].in? %w[ CACHE SCHEMA ]
      count += 1
    end
  }

  ActiveSupport::Notifications.subscribed(counter_f, "sql.active_record", &block)

  count
end

Usage is just:

c = count_queries do
  SomeModel.first
end