Edit file File name : eventmachine.rb Content : require 'eventmachine' require 'mysql2/em' EM.run do client1 = Mysql2::EM::Client.new defer1 = client1.query "SELECT sleep(3) as first_query" defer1.callback do |result| puts "Result: #{result.to_a.inspect}" end client2 = Mysql2::EM::Client.new defer2 = client2.query "SELECT sleep(1) second_query" defer2.callback do |result| puts "Result: #{result.to_a.inspect}" end end Save