Hướng dẫn bắt đầu bằng RoR: Rake db: di chuyển phương thức chưa xác định 'tham chiếu'

Question

Tôi đang theo dõi RoR Getting Started tutorial. Sau khi tạo bài đăng, tôi hiện đang thêm mô hình thứ hai để tạo nhận xét. Tuy nhiên, khi tôi cố gắng cào db:migrate tôi có được điều này:

** Invoke db:migrate (first_time) 
** Invoke environment (first_time) 
** Execute environment 
** Invoke db:load_config (first_time) 
** Invoke rails_env (first_time) 
** Execute rails_env 
** Execute db:load_config 
** Execute db:migrate 
== CreateComments: migrating ================================================= 
-- create_table(:comments) 
rake aborted! 
An error has occurred, this and all later migrations canceled: 

undefined method `reference' for #<ActiveRecord::ConnectionAdapters::TableDefinition:0x1084a24d8> 
/Users/Fryed/rails/blog/db/migrate/20120710225337_create_comments.rb:6:in `change' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/connection_adapters/abstract/schema_statements.rb:160:in `create_table' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:466:in `send' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:466:in `method_missing' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:438:in `say_with_time' 
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/benchmark.rb:293:in `measure' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:438:in `say_with_time' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:458:in `method_missing' 
/Users/Fryed/rails/blog/db/migrate/20120710225337_create_comments.rb:3:in `change' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:407:in `migrate' 
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/benchmark.rb:293:in `measure' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:407:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/connection_adapters/abstract/connection_pool.rb:123:in `with_connection' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:389:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:528:in `__send__' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:528:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:720:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:775:in `call' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:775:in `ddl_transaction' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/transactions.rb:208:in `transaction' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:775:in `ddl_transaction' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:719:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:700:in `each' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:700:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:570:in `up' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/migration.rb:551:in `migrate' 
/Library/Ruby/Gems/1.8/gems/activerecord-3.2.6/lib/active_record/railties/databases.rake:153 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `execute' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `invoke_with_call_chain' 
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `top_level' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `top_level' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `run' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run' 
/Library/Ruby/Gems/1.8/gems/rake-0.9.2.2/bin/rake:33 
/usr/bin/rake:23:in `load' 
/usr/bin/rake:23 
Tasks: TOP => db:migrate 

Tôi đang chạy:

Rake 0.9.2.2. Ruby 1.8.7 Đường ray 3.2.6

Answer 1

Di chuyển có tham chiếu sử dụng trợ giúp references, có thể bạn chỉ cần quên đặt s cuối cùng.

Tìm các vi phạm di cư db/migrate/20120710225337_create_comments.rb và thay đổi từ reference để references