安装mysql2 gem错误

Question

我通过macport安装了ruby和ruby gems，但是gem列表不包含mysql2。 那么我如何在“ / opt / local / bin / gem”里面的gem列表中安装mysql2 gem？

另外，什么是mysql2 gem？ 我有mysql gem，只想使用mysql，不太确定mysql2是什么意思。 当我尝试在应用程序上启动webrick时，它给我一个mysql2错误。

更新：我运行sudo gem install mysql2并得到以下信息：

构建本机扩展。 这可能需要一段时间...成功安装了mysql2-0.2.7 1个gem已安装正在安装mysql2-0.2.7的ri文档...

封闭类Client的类/模块'mMysql2'

封闭类Result的类/模块'mMysql2'未知为mysql2-0.2.7安装RDoc文档...

封闭类Client的类/模块'mMysql2'

封闭类Result的类/模块'mMysql2'

假设安装了mysql2，即使我没有尝试在我的应用中启动webrick时，文档也没有出现以下错误。

Rails服务器：

/opt/local/lib/ruby/gems/1.8/gems/mysql2-0.2.7/lib/mysql2/mysql2.bundle：dlopen（/opt/local/lib/ruby/gems/1.8/gems/mysql2-0.2。 7 / lib / mysql2 / mysql2.bundle，9）：库未加载：libmysqlclient.18.dylib（LoadError）
引用自：/opt/local/lib/ruby/gems/1.8/gems/mysql2-0.2.7/lib/mysql2/mysql2.bundle原因：找不到映像-/opt/local/lib/ruby/gems/1.8/ /opt/local/lib/ruby/gems/1.8/gems/mysql2-0.2.7/lib/mysql2.rb:8来自/ opt / local /中的gems / mysql2-0.2.7 / lib / mysql2 / mysql2.bundle lib / ruby​​ / gems / 1.8 / gems / bundler-1.0.7 / lib / bundler / runtime.rb：64：in require' from /opt/local/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in require'来自/opt/local/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62 each' from /opt/local/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in require'from /opt/local/lib/ruby/gems/1.8/gems/ bundler-1.0.7 / lib / bundler / runtime.rb：51： each' from /opt/local/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in要求中'来自/opt/local/lib/ruby/gems/1.8/gems/bundler-1.0.7/lib/bundler.rb:112:in require' from /Users/summer/Sites/simple_cms/config/application.rb:7 from /opt/local/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands.rb:28:in require' from /Users/summer/Sites/simple_cms/config/application.rb:7 from /opt/local/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands.rb:28:in require'来自/opt/local/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands.rb:28来自/ opt / local / lib / ruby / gems / 1.8 / gems / railties-3.0.7 / lib / rails / commands.rb：27：in tap' from /opt/local/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands.rb:27 from script/rails:6:in script / rails：6

Answer 1

为了对可用的远程gem执行搜索，请运行命令gem search mysql2 -r（注意末尾的-r）

*远程宝石*

activerecord-mysql2legacydb-adapter（0.2.0）activerecord-mysql2spatial-adapter（0.3.2）em_mysql2_connection_pool（0.0.5）ghazel-mysql2（0.2.6.3）mysql2（0.2.7，0.2.6 x86-mingw32 x86-mswin32- 60）mysql2_bigint（0.2.6.1）mysql2_model（0.1.2）mysql2mysql（0.0.2）mysql2psql（0.1.0）mysql2xxxx（0.0.4）

从gem列表中，您应该选择mysql2并运行sudo gem install mysql2

Answer 2

据我所知，两个gem（mysql和mysql2）之间的区别之一是mysql2与UTF-8更好地兼容。 这是一篇关于它的文章 。

要安装mysql2 gem，只需运行：

gem install 'mysql2'