Question

ruby2.1.3无法连接mysql

win8.1 x64 zh_cn ，ruby 2.1.3 x64 win installer安装，devkit已安装 DevKit-mingw64-64-4.7.2-20130224-1432-sfx
问题来了：
require mysql找不到，于是安装mysql的dbi，gem install mysql，报错信息如下，请问怎么破？谢谢！
D:\Ruby21-x64\devkit>gem install mysql
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing mysql:
ERROR: Failed to build gem native extension.

d:/Ruby21-x64/bin/ruby.exe extconf.rb
checking for main() in -llibmysql... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.

Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=d:/Ruby21-x64/bin/ruby
--with-mysql-dir
--without-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib
--without-mysql-lib=${mysql-dir}/lib
--with-libmysqllib
--without-libmysqllib

extconf failed, exit code 1

Gem files will remain installed in d:/Ruby21-x64/lib/ruby/gems/2.1.0/gems/mysql-
2.9.1 for inspection.
Results logged to d:/Ruby21-x64/lib/ruby/gems/2.1.0/extensions/x64-mingw32/2.1.0
/mysql-2.9.1/gem_make.out
d:/Ruby21-x64/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require': 126: 找不到指定的模块。 - d:/Ruby21-x64/lib/ruby/gems/2.1.0/extensions/x64-mingw32/2.1.0/mysql-2.9.1/mysql/mysql_api.so (LoadError)
程序很简单，就是require “mysql”看看能不能成功。

Answer 1

ruby在windows下使用mysql要注意

1. 要装mysql2

2. 要指定mysql-connector的目录，注意你的目录可能跟我的不一样

gem install mysql2 --platform=ruby -- '--with-mysql-dir="C:\mysql-connector\"'

我当时用的是ruby2.1.1，不过应该差别不大

追问

非常感谢你的回答，我提问后google了一下，尝试了几种方法，你说的这个确实解决问题了，mysql的gem安装成功，但是执行程序仍会报错，如下，请问是啥问题？

见原提问，谢谢！

追答

require 'mysql2'啊。现在不都用mysql2吗, rails new xxxx --database=mysql默认都用mysql2