“要求”：无法加载这样的文件-- mysql2 2/mysql2 2

Question

在遇到困难之后，成功地安装了mysql2 v0.4.2

gem install mysql2 -v '0.4.2' -- --srcdir=/usr/local/mysql/include

现在我在运行bundle exec rails s时遇到了以下错误

`require': cannot load such file -- mysql2/mysql2 (LoadError)
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/mysql2-0.4.2/lib/mysql2.rb:31:in `<top (required)>'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:82:in `require'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:82:in `block (2 levels) in require'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:77:in `each'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:77:in `block in require'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:66:in `each'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler/runtime.rb:66:in `require'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/bundler-1.15.4/lib/bundler.rb:108:in `require'
    from /Users/jmayer/workspace/sekai-property/config/application.rb:8:in `<top (required)>'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:78:in `require'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:78:in `block in server'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `tap'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `server'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
    from /Users/jmayer/.rvm/gems/ruby-2.3.1/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
    from bin/rails:4:in `require'
    from bin/rails:4:in `<main>'

rails -v
Rails 4.2.5

ruby -v
ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-darwin18]

我已经尝试了在堆栈溢出中发现的关于错误的每一件事，但是没有运气。

我只是试图启动一个开发服务器，创建一个数据库，等等。

Answer 1

由于您使用的是bundle exec，所以它只考虑到Gemfile中存在的宝石，所以您需要将它放在那里。

包括

gem mysql2 

在Gemfile中(它存在于项目的根目录中)

那就跑

bundle install

然后你就可以跑了

bundle exec rails s