rake db：schema：load找不到表格

Question

編輯來自normalocity：我的答案還沒有能夠解決這個問題，所以我發佈了一個替代解決方案的賞金。

---

原題：

我開始一個星期前在Rails項目工作，不斷變化的多次使用的遷移數據庫模式。昨天我嘗試使用這些命令從頭開始創建我的數據庫（研究與開發環境在默認配置）：

rake db:drop 
rake db:create 
rake db:schema:load 

使用--trace選項裝載模式，當我得到這個消息：

** Invoke db:schema:load (first_time) 
** Invoke environment (first_time) 
** Execute environment 
rake aborted! 
Could not find table 'galleries' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/sqlite_adapter.rb:439:in `table_structure' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/sqlite_adapter.rb:322:in `columns' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:95:in `block (2 levels) in initialize' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:185:in `with_connection' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:92:in `block in initialize' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:106:in `yield' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:106:in `default' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:106:in `block in initialize' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/base.rb:717:in `yield' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/base.rb:717:in `default' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/base.rb:717:in `columns_hash' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/locking/optimistic.rb:145:in `locking_enabled?' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/relation.rb:110:in `to_a' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/relation/finder_methods.rb:159:in `all' 
/var/lib/gems/1.9.1/gems/activerecord-3.1.3/lib/active_record/base.rb:441:in `all' 
/home/fabien/Dropbox/portfolio/app/admin/photos.rb:10:in `block in <top (required)>' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/dsl.rb:13:in `instance_eval' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/dsl.rb:13:in `run_registration_block' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/namespace.rb:171:in `parse_registration_block' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/namespace.rb:50:in `register' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/application.rb:87:in `register' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin.rb:60:in `register' 
/home/fabien/Dropbox/portfolio/app/admin/photos.rb:1:in `<top (required)>' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `block in load' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `block in load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:640:in `new_constants_in' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/application.rb:132:in `block in load!' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/application.rb:132:in `each' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/application.rb:132:in `load!' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/application.rb:155:in `routes' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin.rb:63:in `routes' 
/home/fabien/Dropbox/portfolio/config/routes.rb:9:in `block in <top (required)>' 
/var/lib/gems/1.9.1/gems/actionpack-3.1.3/lib/action_dispatch/routing/route_set.rb:258:in `instance_exec' 
/var/lib/gems/1.9.1/gems/actionpack-3.1.3/lib/action_dispatch/routing/route_set.rb:258:in `eval_block' 
/var/lib/gems/1.9.1/gems/actionpack-3.1.3/lib/action_dispatch/routing/route_set.rb:235:in `draw' 
/home/fabien/Dropbox/portfolio/config/routes.rb:1:in `<top (required)>' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `block in load' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `block in load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:640:in `new_constants_in' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application/routes_reloader.rb:29:in `block in load_paths' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application/routes_reloader.rb:29:in `each' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application/routes_reloader.rb:29:in `load_paths' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application/routes_reloader.rb:13:in `reload!' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application.rb:87:in `reload_routes!' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/reloader.rb:34:in `reload!' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/reloader.rb:28:in `block in initialize' 
/ var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/file_update_checker.rb:32:in `call' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/file_update_checker.rb:32:in `execute_if_updated' 
/var/lib/gems/1.9.1/gems/activeadmin-0.3.4/lib/active_admin/reloader.rb:45:in `block in attach!' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/callbacks.rb:404:in `_run_prepare_callbacks' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/callbacks.rb:81:in `run_callbacks' 
/var/lib/gems/1.9.1/gems/actionpack-3.1.3/lib/action_dispatch/middleware/reloader.rb:46:in `prepare!' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application/finisher.rb:41:in `block in <module:Finisher>' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/initializable.rb:30:in `instance_exec' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/initializable.rb:30:in `run' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/initializable.rb:55:in `block in run_initializers' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/initializable.rb:54:in `each' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/initializable.rb:54:in `run_initializers' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application.rb:96:in `initialize!' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/railtie/configurable.rb:30:in `method_missing' 
/home/fabien/Dropbox/portfolio/config/environment.rb:5:in `<top (required)>' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `require' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `block in require' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `block in load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:640:in `new_constants_in' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `load_dependency' 
/var/lib/gems/1.9.1/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `require' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application.rb:83:in `require_environment!' 
/var/lib/gems/1.9.1/gems/railties-3.1.3/lib/rails/application.rb:193:in `block (2 levels) in initialize_tasks' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `block in execute' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain' 
/usr/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:176:in `block in invoke_prerequisites' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `each' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `invoke_prerequisites' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:157:in `block in invoke_with_call_chain' 
/usr/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block (2 levels) in top_level' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block in top_level' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `block in run' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run' 
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/bin/rake:33:in `<top (required)>' 
/usr/local/bin/rake:19:in `load' 
/usr/local/bin/rake:19:in `<main>' 
Tasks: TOP => db:schema:load => environment 

鐵軌初學者，我不知道如何解決這個問題，尤其是我的schema.rb有創建畫廊表的命令。

我的代碼可以在這裏找到：https://github.com/fabienengels/portfolio

Answer 1

您需要修改/app/admin/photos.rb

# /app/admin/photos.rb 
index :as => :grid, :columns => 6 do |photo| 
    Gallery.all.each do |gallery| 
     scope gallery.slug.to_sym do |photos| 
     photos.where(:gallery_id => gallery) 
     end 
    end 
    # link_to(image_tag(photo.file.url(:thumb)), admin_photo_path(photo)) 
end 

，你需要把這些代碼的index塊內。我在那裏註釋掉了你的鏈接標籤。我會留給你想出如何設計你的網格/塊/什麼。只要確保它在索引範圍內即可。祝你好運。

Answer 2

我以前從未使用過ActiveAdmin，但是從文檔，但似乎你只能在一個ActiveAdmin.register塊內引用單個模型，或者你根本避風港」 t使Gallery模型在該文件內部可見。

因此，在app/admin/photos.rb，你必須

ActiveAdmin.register Photo do 
    ... 

    Gallery.all.each do |gallery|    # <= this is invalid, because this file 
    scope gallery.slug.to_sym do |photos| # doesn't know what `Gallery` (and therefore 
     photos.where(:gallery_id => gallery) # `galleries` table`) is referring to 
    end 
    end 

    .... 
end 

我不知道，即使你可怎麼辦嵌套ActiveAdmin註冊，或者，但你得到的錯誤消息告訴你，Gallery是無法在此文件範圍內訪問，因此，它就像是「什麼」畫廊表？我們在這裏沒有「畫廊」表。「

所以，你可以嘗試這兩件事情之一來解決它，看看會發生什麼 - 希望這是任何答案，或將導致你的答案：

• 在app/admin/photos.rb的最頂端文件中添加這個確切的行：
  • require '../models/gallery'
• 如果不工作，然後代替Gallery.all.each...嘗試
  • ActiveAdmin.register Gallery do其次是同一塊

Answer 3

所以問題是，當你的應用程序加載時，它加載了你的activeadmin的東西。這反過來結束運行Gallery.all知道什麼範圍設置。

運行類似schema:load的耙子任務仍然會加載應用程序，所以它仍然在嘗試執行Gallery.all，但是您剛剛刪除/重新創建了數據庫，因此完全可以說該表格不在那裏。

你希望能夠做的是告訴ActiveAdmin不要打擾自己配置，因爲你只是在運行一些遷移。

幸運的是，在這些情況下設置了全局變量$rails_rake_task。如果$rails_rake_task爲true，或者如果這不起作用，並且沒有執行任何activeadmin配置（例如app/admin/photos中的內容），則$rails_rake_task爲true，則嘗試不在active_admin初始程序中運行代碼。