Windows 上使用 sqlite3-ruby 进行未初始化常量编码

Question

在新机器上，使用 Windows 的一键安装程序安装 ruby​​。安装了 Rails 2.3.2 和所有相关的 gem，然后安装了 sqlite3 二进制文件（到 c:\ruby\bin 文件夹中）。最后我做了 gem install sqlite3-ruby -v=1.2.3 （这显然是适用于 Windows 的最新版本）

当我运行 rake db:migrate 时会发生此错误或者在运行时触摸任何 ActiveRecord 对象时。

错误如下所示：

** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:migrate
rake aborted!
**uninitialized constant Encoding**  <----

任何解决此错误的帮助将不胜感激！

跟踪：

 C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.2/lib/active_support/dependencies.rb:443:in `load_missing_constant'
    C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.2/lib/active_support/dependencies.rb:80:in `const_missing'
    C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.2/lib/active_support/dependencies.rb:92:in `const_missing'
    C:/Ruby/lib/ruby/gems/1.8/gems/sqlite3-0.0.3/lib/sqlite3/encoding.rb:9:in `find'
    C:/Ruby/lib/ruby/gems/1.8/gems/sqlite3-0.0.3/lib/sqlite3/database.rb:69:in `initialize'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/sqlite3_adapter.rb:13:in `new'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/sqlite3_adapter.rb:13:in `sqlite3_connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:223:in `send'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:223:in `new_connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:245:in `checkout_new_connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:188:in `checkout'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:184:in `loop'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:184:in `checkout'
    C:/Ruby/lib/ruby/1.8/monitor.rb:242:in `synchronize'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:183:in `checkout'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:98:in `connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:326:in `retrieve_connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_specification.rb:123:in `retrieve_connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/connection_specification.rb:115:in `connection'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/migration.rb:435:in `initialize'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/migration.rb:400:in `new'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/migration.rb:400:in `up'
    C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/migration.rb:383:in `migrate'
    C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.2/lib/tasks/databases.rake:116
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `call'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `execute'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `each'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `execute'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:597:in `invoke_with_call_chain'
    C:/Ruby/lib/ruby/1.8/monitor.rb:242:in `synchronize'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:583:in `invoke'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `each'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2001:in `run'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
    C:/Ruby/lib/ruby/gems/1.8/gems/rake-0.8.7/bin/rake:31
    C:/Ruby/bin/rake:19:in `load'
    C:/Ruby/bin/rake:19

Answer 1

如果您查看回溯，会发现问题不是 sqlite3-ruby 而是您安装的另一个 gem：

C:/Ruby/lib/ruby/gems/1.8/gems/sqlite3-0.0.3/lib/sqlite3/encoding.rb:9:in `find'
C:/Ruby/lib/ruby/gems/1.8/gems/sqlite3-0.0.3/lib/sqlite3/database.rb:69:in `initialize'

请卸载 sqlite3 gem (gem uninstall sqlite3)，因为似乎会干扰加载机制。

sqlite3-ruby gem 版本 1.2.5 已针对 Windows 进行更新，应该可以开箱即用。

我建议阅读替代 One-Click 的新 RubyInstaller 的教程：

教程

并安装最新的 RC1 版本，而不是来自此处的一键式

希望这会有所帮助。