ruby-on-rails - `require' : cannot load such file -- mysql2/mysql2

Question

使用困难但成功安装 mysql2 v 0.4.2 后

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

我现在在运行 bundle execrails s

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>'

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找到的有关该错误的所有方法，但没有成功。

我只是想启动一个开发服务器，创建一个数据库等。

Answer 1

Since you are using bundle exec it is only taking in account gems present in Gemfile, so you need to put it there.

包括

gem mysql2 

在您的 Gemfile 中(位于项目的根目录中)

然后运行

bundle install

然后就可以运行了

bundle exec rails s