Ruby on rails `要求'；：无法加载这样的文件--mysql2/mysql2

在遇到困难但成功安装mysql2 v 0.4.2之后

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

我现在在运行

bundle exec rails时遇到以下错误

`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>'

我已经尝试了我在堆栈溢出上发现的关于错误的每一件事，但是没有运气

我只是想启动一个开发服务器，创建一个数据库，等等

因为您使用的是
bundle exec
，所以它只考虑gems
存在于Gemfile中，因此您需要将其放在那里

包括

gem mysql2 

在Gemfile中（位于项目的根目录中）

然后跑

bundle install

然后你就可以跑了

bundle exec rails s

谢谢你的回复，很遗憾我没有列出很多细节。mysql2在这个文件中。在运行
gem安装…
之后，我已经运行了
bundle安装。此外，我在没有bundle exec的情况下运行了
rails s
，
rails 5.2.2
-
ruby 2.6.1p33（2019-01-30修订版66950）[x86_64-darwin18]
和
mysql2（0.5.2）
bundle exec rails
不工作（我在我的
gem文件
gem'mysql2'，'>=0.4.4'，'<0.6.0'
bundle install

bundle exec rails s