Simple benchmark for explaining database indexes

benchmark.rb

require 'mysql2'
require 'benchmark'

user      = 'USER'
password  = 'PASSWORD'
database  = 'benchmark'

client = Mysql2::Client.new(host: 'localhost', username: user, password: password, database: database)

Benchmark.bmbm do |x|
  x.report do
    (0..99).each do
      client.query 'SELECT u.first_name, u.last_name, u.email FROM users u where company_id = 100094'
    end
  end
end