ruby安装mysql2模块

$ sudo gem install mysql2 -- '--with-mysql-config=/opt/mysql/bin/mysql_config'

测试

$ cat testmysql2.rb 

require 'mysql2'

client = Mysql2::Client.new(:host => "127.0.0.1", :username => "用户名",:password=>"密码",:database=>"数据库名")

results = client.query("select * from 表");

results.each do |hash|

  puts hash.map { |k,v| "#{k} = #{v}" }.join(", ")

end