rake db:schema:load 找不到表

Question

来自normalocity的编辑：我的答案无法解决这个问题，所以我'我发布了替代解决方案的赏金。

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原始问题：

我一周前开始从事 Rails 项目，使用迁移多次更改数据库架构。昨天，我尝试使用这些命令从头开始创建数据库（开发环境、默认配置）：

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

使用 --trace 选项加载架构时收到此消息：

** 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

作为 Rails 初学者，我不知道如何解决这个问题，尤其是我的架构.rb 有创建画廊表的命令。

我的代码可以在这里找到： https://github.com/fabienengels/portfolio

Answer 1

您需要修改您的 /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

您需要将该代码放入 index 块中。我在那里注释掉了你的链接标签。我将让您自行决定如何设计网格/块/其他内容。只需确保它在索引范围内即可。祝你好运。

Answer 2

所以问题是，当您的应用程序加载时，它会加载您的 activeadmin 内容。反过来，最终会运行 Gallery.all 来了解要设置的范围。

运行诸如 schema:load 这样的 rake 任务仍然会加载应用程序，因此它仍在尝试执行 Gallery.all 但您刚刚删除/重新创建了数据库，因此这是非常正确的说桌子不在那里。

您希望能够做的是告诉 ActiveAdmin 不要费心配置自身，因为您只是在运行一些迁移。

幸运的是，在这些情况下设置了一个全局变量$rails_rake_task。每当 $rails_rake_task 为 true 时，我会尝试不运行 active_admin 初始化程序中的代码，或者如果这不起作用，也不执行任何 activeadmin 配置（例如 app/admin/photos 中的内容）如果 <代码>$rails_rake_task 为真。

Answer 3

我以前从未使用过 ActiveAdmin，但是从文档来看，您似乎只能在 ActiveAdmin.register 块中引用单个模型，或者您根本没有创建 Gallery 模型在此文件内可见。

因此，在 app/admin/photos.rb 中，

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

我不确定如何进行嵌套 ActiveAdmin 注册，或者即使可以，但错误消息我们得到的信息是告诉您 Gallery 在此文件的范围内无法访问，因此，就像“什么‘画廊’表？我们这里没有‘画廊’表。”。

因此，您可以尝试这两件事之一来解决它，看看会发生什么 - 希望这就是答案，或者会引导您找到答案：

• 在 app/admin/photos.rb< 的最顶部/code> 文件，添加这一行：
  • 需要“../models/gallery”

• 如果这不起作用，则尝试使用 Gallery.all.each...
  • ActiveAdmin.register Gallery do 后跟同一块