Ruby 连接 Mysql – MySql2

Ruby 连接 Mysql - MySql2前面一章节我们介绍了 Ruby DBI 的使用。这章节我们技术 Ruby 连接 Mysql 更高效的驱动 mysql2，目前也推荐使用这种方式连接 MySql。安装 mysql2 驱动：gem install mysql2你需要使用 –with-mysql-config 配置 mysql_config 的路径，如： –with-mysql-config=/some/random/path/bin/mysql_config。连接连接数据库语法如下：client = Mysql2:





:





Client.new(:





host => "localhost", :





username => "root")更多参数可以查看 http:





//api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/MysqlAdapter.html。查询results = client.query("SELECT * FROM users WHERE group='githubbers'")特殊字符转义escaped = client.escape("gi'thu\"bbe\0r's")results = client.query("SELECT * FROM users WHERE group='





#{escaped}'")计算结果集返回的数量:





results.count迭代结果集：results.each do |row|





# row 是哈希





# 键值是数据库字段





# 值都是对应 MySQL中数据puts row["id"]





# row["id"].class == Fixnumif row["dne"]





# 不存在则是 nilputs row["dne"]endend实例





#!/usr/bin/ruby -wrequire 'mysql2'client = Mysql2:





:





Client.new(:





host => '127.0.0.1',





# 主机:





username => 'root',





# 用户名:





password => '123456',





# 密码:





database => 'test',





# 数据库:





encoding => 'utf8'





# 编码)results = client.query("SELECT VERSION()")results.each do |row|puts rowend以上实例运行输出结果为：{"VERSION()"=>"5.6.21"}连接选项Mysql2:





:





Client.new(:





host,:





username,:





password,:





port,:





database,:





socket = '/path/to/mysql.sock',:





flags = REMEMBER_OPTIONS | LONG_PASSWORD | LONG_FLAG | TRANSACTIONS | PROTOCOL_41 | SECURE_CONNECTION | MULTI_STATEMENTS,:





encoding = 'utf8',:





read_timeout = seconds,:





write_timeout = seconds,:





connect_timeout = seconds,:





reconnect = true/false,:





local_infile = true/false,:





secure_auth = true/false,:





default_file = '/path/to/my.cfg',:





default_group = 'my.cfg section',:





init_command => sql)更多内容请参阅：http:





//www.rubydoc.info/gems/mysql2/0.2.3/frames。