使用 MySQL 运行 Rails 服务器时出现错误答案

【问题标题】：Getting errors when running Rails server with MySQL使用 MySQL 运行 Rails 服务器时出现错误
【发布时间】：2017-11-07 00:29:26
【问题描述】：

dani@saeedi:~/Desktop/website/myweb$ rails server
/home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.4.5/lib/mysql2.rb:31:in `require': libmysqlclient.so.20: cannot open shared object file: No such file or directory - /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.4.5/lib/mysql2/mysql2.so (LoadError)
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.4.5/lib/mysql2.rb:31:in `<top (required)>'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:82:in `require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:82:in `block (2 levels) in require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:77:in `each'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:77:in `block in require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:66:in `each'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/runtime.rb:66:in `require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler.rb:108:in `require'
    from /home/dani/Desktop/website/myweb/config/application.rb:7:in `<top (required)>'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:88:in `require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:88:in `block in server'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `tap'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:85:in `server'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-5.0.2/lib/rails/commands.rb:18:in `<top (required)>'
    from /home/dani/Desktop/website/myweb/bin/rails:9:in `require'
    from /home/dani/Desktop/website/myweb/bin/rails:9:in `<top (required)>'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/client/rails.rb:28:in `load'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/client/rails.rb:28:in `call'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/client/command.rb:7:in `call'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/client.rb:30:in `run'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/bin/spring:49:in `<top (required)>'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/binstub.rb:31:in `load'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.1/lib/spring/binstub.rb:31:in `<top (required)>'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/site_ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
    from /home/dani/.rbenv/versions/2.4.0/lib/ruby/site_ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
    from /home/dani/Desktop/website/myweb/bin/spring:15:in `<top (required)>'
    from bin/rails:3:in `load'
    from bin/rails:3:in `<main>'

【问题讨论】：

从终端运行sudo apt-get install libmysqlclient-dev
发帖小贴士： (1) 格式化控制台输出和日志文件，编辑器中有一个按钮； (2) 除了标题之外没有上下文的错误转储看起来并没有做出很大的努力，并且可能会吸引反对票，(3) 读者知道您需要帮助，所以“请帮助我”通常只会被理解为乞讨，（4）向我们展示您为解决问题所做的研究。您是否搜索过错误？
Plenty of duplicates here.

标签： mysql ruby-on-rails ruby ubuntu

【解决方案1】：

可能你的系统中没有安装 libmysqlclient。使用以下命令安装它：

sudo apt-get install libmysqlclient-dev

干杯！

【讨论】：