无法从 Sequel gem 连接 mysql

Question

当我尝试从 Sequel 连接到 MySQL 时。 我收到这些错误：

require 'rubygems'
        require 'sequel'
        DB = Sequel.connect(:adapter => 'mysql', :user => 'root', :host => 'localhost', :database => 'scanty',:password=>'xx')
        DB.tables
    Sequel::DatabaseConnectionError: NameError uninitialized constant Mysql::CLIENT_MULTI_RESULTS
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/adapters/mysql.rb:98:in `connect'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/database.rb:92:in `initialize'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:166:in `call'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:166:in `make_new'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:153:in `available'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:144:in `acquire'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:143:in `synchronize'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:143:in `acquire'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/connection_pool.rb:105:in `hold'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/database.rb:471:in `synchronize'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/adapters/mysql.rb:128:in `execute'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/dataset.rb:314:in `execute'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/adapters/mysql.rb:342:in `execute'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/adapters/mysql.rb:298:in `fetch_rows'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/dataset.rb:185:in `each'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/dataset/convenience.rb:156:in `map'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/dataset/convenience.rb:156:in `map'
        from /opt/local/lib/ruby/gems/1.8/gems/sequel-3.2.0/lib/sequel/adapters/shared/mysql.rb:60:in `tables'
        from (irb):6irb(main):007:0> Sequel::DatabaseConnectionError: NameErro

Answer 1

需要安装原生MySQL驱动，纯ruby驱动不兼容Sequel。

根据您的 Ruby 安装，只需执行 gem install mysql 就足够了。 但是，如果纯 Ruby mysql.rb 文件已位于 Ruby 加载路径中，则需要将其从加载路径中删除或在调用 Sequel 之前使用 gem('mysql')。连接。

Answer 2

您缺少 :host=>'localhost' 或您的主机。

另外，这纯粹是出于性能原因，您应该尝试启用 :compress。 它可以节省大量带宽。

http://sequel.rubyforge.org/rdoc/files/doc/opening_databases_rdoc。 html

编辑：好吧，如果不是主机，也许是冲突？ 请参阅 http://groups.google.com/group /sequel-talk/browse_thread/thread/ee39640a92351f1?pli=1。 另http://www.mail-archive.com/< span class="__cf_email__" data-cfemail="d3a0b6a2a6b6bffea7b2bfb893b4bcbcb4bfb6b4a1bca6a3a0fdb0bcbe">[电子邮件受保护]/msg02275.html