安装mysql2适配器时出错:请安装mysql2适配器：“`gem安装activerecord 2-适配器”(无法加载此类文件-mysql2 2/mysql2 2)

Question

当运行Redbreine2.3-稳定时，我会收到此错误，随后无法成功安装mysql2适配器。

这是一个错误：

    Please install the mysql2 adapter: `gem install activerecord-mysql2-adapter` (cannot load such file -- mysql2/mysql2)

当我运行网站，通过乘客，运行rake db:迁移时，我得到了这个

适配器安装如下：

创业板列表

*本地宝石*

actionmailer (3.2.13)
actionpack (3.2.13)
activemodel (3.2.13)
activerecord (3.2.13)
activerecord-mysql2-adapter (0.0.3)
activeresource (3.2.13)
activesupport (3.2.13)
afm (0.2.0)
arel (3.0.2)
Ascii85 (1.0.2)
bigdecimal (1.1.0)
builder (3.0.4, 3.0.0)
bundler (1.3.4)
coderay (1.0.9)
daemon_controller (1.1.2)
daemons (1.1.9)
erubis (2.7.0)
eventmachine (1.0.3)
fastthread (1.0.7)
hashery (2.1.0)
hike (1.2.1)
holidays (1.0.5)
i18n (0.6.1)
icalendar (1.2.3)
io-console (0.3)
journey (1.0.4)
jquery-rails (2.0.3)
json (1.7.7, 1.5.4)
mail (2.5.3)
mime-types (1.21)
minitest (4.7.0, 2.5.1)
multi_json (1.7.2)
mysql2 (0.3.11)
net-ldap (0.3.1)
nokogiri (1.5.9)
open-uri-cached (0.0.5)
passenger (3.0.19)
pdf-reader (1.3.2)
polyglot (0.3.3)
prawn (0.12.0)
rack (1.4.5)
rack-cache (1.2)
rack-openid (1.3.1)
rack-ssl (1.3.3)
rack-test (0.6.2)
rails (3.2.13)
railties (3.2.13)
rake (10.0.4, 0.9.2.2)
rdoc (3.12.2, 3.9.4)
ruby-openid (2.1.8)
ruby-rc4 (0.1.5)
rubygems-update (2.0.3)
sprockets (2.2.2)
thin (1.5.1)
thor (0.17.0)
tilt (1.3.6)
treetop (1.4.12)
ttfunk (1.0.3)
tzinfo (0.3.37)

红宝石-v

ruby 1.9.3p194 (2012-04-20 revision 35410) [x86_64-linux]

宝石env

- RUBYGEMS VERSION: 2.0.3
- RUBY VERSION: 1.9.3 (2012-04-20 patchlevel 194) [x86_64-linux]
- INSTALLATION DIRECTORY: /usr/local/lib/ruby/gems/1.9.1
- RUBY EXECUTABLE: /usr/local/bin/ruby
- EXECUTABLE DIRECTORY: /usr/local/bin
- RUBYGEMS PLATFORMS:
  - ruby
  - x86_64-linux
- GEM PATHS:
   - /usr/local/lib/ruby/gems/1.9.1
   - /root/.gem/ruby/1.9.1
- GEM CONFIGURATION:
   - :update_sources => true
   - :verbose => true
   - :backtrace => false
   - :bulk_threshold => 1000
- REMOTE SOURCES:
   - https://rubygems.org/

我试着通过编辑Gemfile来迫使redmine改为rails3.2.2，这里有一个建议：

Rails 3.2.2 mysql2 adapter Error

备注

我不得不使用下面的命令强制gem mysql2包安装工作(我收到了关于errormsg.h的错误)。

sudo gem install activerecord-mysql2-adapter -- --srcdir=/usr/include/mysql/

有什么想法吗？

Answer 1

在Gemfile中包括mysql2 gem，并将database.yml中的适配器更改为mysql2，然后执行包安装。它会解决你的问题。