当我运行bundle exec rake db：migrate --trace时，我收到以下错误。
C:\Sites\rails_projects\sample_app>bundle exec rake db:migrate --trace
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
undefined method `migration_error=' for ActiveRecord::Base:Class
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.14/lib/act
ive_record/dynamic_matchers.rb:55:in `method_missing'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.14/lib/act
ive_record/railtie.rb:72:in `block (3 levels) in <class:Railtie>'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.14/lib/act
ive_record/railtie.rb:71:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.14/lib/act
ive_record/railtie.rb:71:in `block (2 levels) in <class:Railtie>'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/lazy_load_hooks.rb:36:in `instance_eval'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/lazy_load_hooks.rb:36:in `execute_hook'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/lazy_load_hooks.rb:26:in `block in on_load'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/lazy_load_hooks.rb:25:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/lazy_load_hooks.rb:25:in `on_load'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.14/lib/act
ive_record/railtie.rb:67:in `block in <class:Railtie>'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/i
nitializable.rb:30:in `instance_exec'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/i
nitializable.rb:30:in `run'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/i
nitializable.rb:55:in `block in run_initializers'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/i
nitializable.rb:54:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/i
nitializable.rb:54:in `run_initializers'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/a
pplication.rb:136:in `initialize!'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/r
ailtie/configurable.rb:30:in `method_missing'
C:/Sites/rails_projects/sample_app/config/environment.rb:5:in `<top (required)>'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/dependencies.rb:251:in `require'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/dependencies.rb:251:in `block in require'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/dependencies.rb:236:in `load_dependency'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-3.2.14/lib/ac
tive_support/dependencies.rb:251:in `require'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/a
pplication.rb:103:in `require_environment!'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.14/lib/rails/a
pplication.rb:305:in `block (2 levels) in initialize_tasks'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:236:in `call'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:236:in `block in execute'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:231:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:231:in `execute'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:175:in `block in invoke_with_call_chain'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:168:in `invoke_with_call_chain'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:197:in `block in invoke_prerequisites'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:195:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:195:in `invoke_prerequisites'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:174:in `block in invoke_with_call_chain'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:168:in `invoke_with_call_chain'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/task.r
b:161:in `invoke'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:149:in `invoke_task'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:106:in `block (2 levels) in top_level'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:106:in `each'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:106:in `block in top_level'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:115:in `run_with_threads'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:100:in `top_level'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:78:in `block in run'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:165:in `standard_exception_handling'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/lib/rake/applic
ation.rb:75:in `run'
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/rake-10.1.0/bin/rake:33:in
`<top (required)>'
C:/RailsInstaller/Ruby1.9.3/bin/rake:23:in `load'
C:/RailsInstaller/Ruby1.9.3/bin/rake:23:in `<main>'
Tasks: TOP => db:migrate => environment
的Gemfile
source 'https://rubygems.org'
gem 'rails', '3.2.14'
gem 'bootstrap-sass', '2.1'
gem 'bcrypt-ruby', '3.0.1'
gem 'faker', '1.0.1'
gem 'will_paginate', '3.0.3'
gem 'bootstrap-will_paginate', '0.0.6'
gem 'jquery-rails', '2.0.2'
group :development, :test do
gem 'sqlite3', '1.3.5'
gem 'rspec-rails', '2.11.0'
gem 'guard-rspec', '1.2.1'
gem 'guard-spork', '1.2.0'
gem 'childprocess', '0.3.6'
gem 'spork', '0.9.2'
end
# Gems used only for assets and not required
# in production environments by default.
group :assets do
gem 'sass-rails', '3.2.5'
gem 'coffee-rails', '3.2.2'
gem 'uglifier', '1.2.3'
end
group :test do
gem 'capybara', '1.1.2'
gem 'factory_girl_rails', '4.1.0'
gem 'cucumber-rails', '1.2.1', :require => false
gem 'database_cleaner', '0.7.0'
# gem 'launchy', '2.1.0'
# gem 'rb-fsevent', '0.9.1', :require => false
# gem 'growl', '1.0.3'
end
group :production do
gem 'pg', '0.12.2'
end
的database.yml
# SQLite version 3.x
# gem install sqlite3
#
# Ensure the SQLite 3 gem is defined in your Gemfile
# gem 'sqlite3'
development:
adapter: sqlite3
database: db/development.sqlite3
pool: 5
timeout: 5000
# 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: &test
adapter: sqlite3
database: db/test.sqlite3
pool: 5
timeout: 5000
production:
adapter: sqlite3
database: db/production.sqlite3
pool: 5
timeout: 5000
cucumber:
<<: *test
我已经检查了类似的帖子，这些解决方案都没有对我有用，所以感谢您提供的任何帮助。
答案 0 :(得分：7)
我在设计多引擎应用程序时多次遇到此错误，它总是发生在引擎中。但是，就我而言，它似乎来自粗心的错误。对于我的引擎，除了database.yml数据库之外，test中没有指定任何数据库环境：
test:
adapter: "mysql2"
database: "test_engine_db"
username: 'root'
password: ''
所以做rake db:migrate让我得到了这个无益的错误：
undefined method `migration_error=' for ActiveRecord::Base:Class
/Users/me/.rvm/gems/ruby-1.9.3-head@mygems/gems/activerecord-3.2.14/lib/active_record/dynamic_matchers.rb:55:in `method_missing'
问题在于我需要指定test环境：
rake db:migrate RAILS_ENV=test
哪个是“没有呃”......但错误信息非常无益。我尝试了一切，包括擦除我的gemset并手动指定一个版本的Rails，但什么也没做。所有问题都在于我缺少RAILS_ENV标志。