For Ruby on Rails. Put it in your config/initializers folder to print the number of queries executed in a controller action, and also raise an exception if that count exceeds a maximum

query_count.rb

module QueryCount
  Max = 10

  module MysqlAdapterExtensions
    def self.included(base)
      base.alias_method_chain :execute, :review
    end

    def execute_with_review(sql, *args)
      if Thread.current[:query_count] && ['select', 'insert', 'update', 'delete'].include?(sql[0 .. 6].downcase.strip)
        Thread.current[:query_count] += 1
        raise "Query count exceeded maximum (#{Max})" if Thread.current[:query_count] > Max
      end
      execute_without_review(sql, *args)
    end
  end

  module ControllerExtensions
    def self.included(base)
      base.alias_method_chain :process, :review
    end

    def process_with_review(*args)
      Thread.current[:query_count] = 0
      result = process_without_review(*args)
      count = Thread.current[:query_count]
      Rails.logger.info "[QueryCount:#{count}] #{args[0].url}"
      result
    end
  end
end

env = ENV['RAILS_ENV']
if env != 'production'
  ActiveRecord::ConnectionAdapters::MysqlAdapter.send(:include, QueryCount::MysqlAdapterExtensions)
  ActionController::Base.send(:include, QueryCount::ControllerExtensions)
end