相关疑难解决方法(0)

我收到这个错误

`establish_connection': Please install the mysql2 adapter: `gem install activerecord-mysql2-adapter` (no such file to load -- active_record/connection_adapters/mysql2_adapter) (RuntimeError)
  from /opt/ruby-enterprise-1.8.7-2010.02/lib/ruby/gems/1.8/gems/activerecord-

这是整个错误和我的配置和gemfile的转储.

我遇到了JSON gem和Ruby 1.9.2的问题.我正在升级到Rails 3.0.3,每当我尝试启动环境时,它都会爆炸.这是一个空的测试项目,只有JSON gem 1.4.6作为依赖项.

/Users/lee/.rvm/gems/ruby-1.9.2-p0/gems/json-1.4.6/lib/json/common.rb:66: [BUG] unknown type 0x22 (0xc given)
ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]

-- control frame ----------
c:0032 p:---- s:0096 b:0096 l:000095 d:000095 CFUNC  :initialize
c:0031 p:---- s:0094 b:0094 l:000093 d:000093 CFUNC  :new
c:0030 p:0085 s:0091 b:0089 l:000088 d:000088 METHOD /Users/lee/.rvm/gems/ruby-1.9.2-p0/gems/json-1.4.6/lib/json/common.rb:66
c:0029 p:0090 s:0081 b:0080 l:000079 d:000079 CLASS  /Users/lee/.rvm/gems/ruby-1.9.2-p0/gems/json-1.4.6/lib/json/ext.rb:11
c:0028 p:0011 s:0078 b:0078 l:000077 d:000077 CLASS  /Users/lee/.rvm/gems/ruby-1.9.2-p0/gems/json-1.4.6/lib/json/ext.rb:6
c:0027 p:0021 s:0076 b:0076 l:000075 d:000075 TOP    /Users/lee/.rvm/gems/ruby-1.9.2-p0/gems/json-1.4.6/lib/json/ext.rb:3
c:0026 p:---- s:0074 b:0074 l:000073 d:000073 FINISH
c:0025 p:---- …