有人可以帮我解决以下错误吗？当我输入rake db：在cmd上创建时我遇到了这些错误。
错误：
rake aborted!
NoMethodError: undefined method `each' for #<String:0x1a1af20>
Tasks: TOP => db:create => db:load_config
(See full trace by running task with --trace)
当我运行rake db：create --trace时，我得到了以下痕迹。
耙子流产了！ NoMethodError：＃的未定义方法`each'任务：TOP =＆gt; db：create =＆gt; DB：load_config （通过使用--trace运行任务查看完整跟踪）
** Invoke db:create (first_time)
** Invoke db:load_config (first_time)
** Execute db:load_config
rake aborted!
NoMethodError: undefined method `each' for #<String:0x1a37888>
C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-4.2.0/lib/active_record/connect
ion_adapters/connection_specification.rb:150:in `resolve_all'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-4.2.0/lib/active_record/connect
ion_handling.rb:69:in `resolve'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-4.2.0/lib/active_record/core.rb
:46:in `configurations='
C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-4.2.0/lib/active_record/railtie
s/databases.rake:5:in `block (2 levels) in <top (required)>'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:240:in `call'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:240:in `block i
n execute'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:235:in `each'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:235:in `execute
'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:179:in `block i
n invoke_with_call_chain'
C:/Ruby193/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:172:in `invoke_
with_call_chain'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:201:in `block i
n invoke_prerequisites'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:199:in `each'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:199:in `invoke_
prerequisites'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:178:in `block i
n invoke_with_call_chain'
C:/Ruby193/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:172:in `invoke_
with_call_chain'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/task.rb:165:in `invoke'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:150:in `
invoke_task'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:106:in `
block (2 levels) in top_level'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:106:in `
each'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:106:in `
block in top_level'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:115:in `
run_with_threads'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:100:in `
top_level'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:78:in `b
lock in run'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:176:in `
standard_exception_handling'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/lib/rake/application.rb:75:in `r
un'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/rake-10.4.2/bin/rake:33:in `<top (required)>
'
C:/Ruby193/bin/rake:23:in `load'
C:/Ruby193/bin/rake:23:in `<main>'
Tasks: TOP => db:create => db:load_config
我的database.yml文件如下所述。
default:&default
adapter:mysql2
encoding:utf8
pool:5
username:root
password:pass
host:localhost
development:<<:*default
database:sqlbook_development
# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:<<:*default
database:sqlbook_test
# As with config/secrets.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password as a unix environment variable when you boot
# the app. Read http://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full rundown on how to provide these environment variables in a
# production deployment.
#
# On Heroku and other platform providers, you may have a full connection URL
# available as an environment variable. For example:
#
# DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
#
# You can use this database configuration with:
#
# production:
# url: <%= ENV['DATABASE_URL'] %>
#
production:<<:*default
database:sqlbook_production
username:sqlbook
password:pass
我正在使用rails版本4.2.0和ruby 1.9.3。请帮我解决此错误。谢谢提前..