所以我有一个预先注册用户的应用程序。未来的用户可以声明他们的个人资料，但管理员必须手动审核。
所以，我有一个表用户和user_revision。如果管理员拒绝了索赔，我需要恢复所做的更改。
我是这样做的：
Followup.find(params[:followup]).user.update_attributes(UserRevision.find(followup.i_nid).attributes)
但由于某些原因突然出现以下错误，我不知道如何解决它：
NoMethodError（未定义的方法`each'代表“”：String）：
编辑：这是完整的跟踪
activerecord (3.2.13) lib/active_record/associations/collection_association.rb:310:in `replace'
activerecord (3.2.13) lib/active_record/associations/collection_association.rb:41:in `writer'
activerecord (3.2.13) lib/active_record/associations/builder/association.rb:51:in `block in define_writers'
activerecord (3.2.13) lib/active_record/attribute_assignment.rb:85:in `block in assign_attributes'
activerecord (3.2.13) lib/active_record/attribute_assignment.rb:78:in `each'
activerecord (3.2.13) lib/active_record/attribute_assignment.rb:78:in `assign_attributes'
activerecord (3.2.13) lib/active_record/persistence.rb:216:in `block in update_attributes'
activerecord (3.2.13) lib/active_record/transactions.rb:313:in `block in with_transaction_returning_status'
activerecord (3.2.13) lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
activerecord (3.2.13) lib/active_record/transactions.rb:208:in `transaction'
activerecord (3.2.13) lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
activerecord (3.2.13) lib/active_record/persistence.rb:215:in `update_attributes'
app/controllers/admin/contractor_controller.rb:66:in `reject'
actionpack (3.2.13) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (3.2.13) lib/abstract_controller/base.rb:167:in `process_action'
actionpack (3.2.13) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.2.13) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.2.13) lib/active_support/callbacks.rb:458:in `_run__3878365275348389010__process_action__3682866777824238009__callbacks'
activesupport (3.2.13) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.13) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.13) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.13) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.13) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.13) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.13) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.13) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.13) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.13) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.13) lib/action_controller/metal/params_wrapper.rb:207:in `process_action'
activerecord (3.2.13) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.13) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.13) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.13) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.13) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.13) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.13) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.13) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.13) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.13) lib/action_dispatch/routing/route_set.rb:612:in `call'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `catch'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.5) lib/rack/etag.rb:23:in `call'
rack (1.4.5) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.5) lib/rack/session/abstract/id.rb:210:in `context'
rack (1.4.5) lib/rack/session/abstract/id.rb:205:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/cookies.rb:341:in `call'
activerecord (3.2.13) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.13) lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.13) lib/active_support/callbacks.rb:405:in `_run__3678957069864581916__call__81522373500476479__callbacks'
activesupport (3.2.13) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.13) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.13) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.13) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.13) lib/rails/rack/logger.rb:32:in `call_app'
railties (3.2.13) lib/rails/rack/logger.rb:16:in `block in call'
activesupport (3.2.13) lib/active_support/tagged_logging.rb:22:in `tagged'
railties (3.2.13) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.5) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.5) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.13) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.5) lib/rack/lock.rb:15:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/static.rb:63:in `call'
railties (3.2.13) lib/rails/engine.rb:479:in `call'
railties (3.2.13) lib/rails/application.rb:223:in `call'
rack (1.4.5) lib/rack/content_length.rb:14:in `call'
railties (3.2.13) lib/rails/rack/log_tailer.rb:17:in `call'
thin (1.5.1) lib/thin/connection.rb:81:in `block in pre_process'
thin (1.5.1) lib/thin/connection.rb:79:in `catch'
thin (1.5.1) lib/thin/connection.rb:79:in `pre_process'
thin (1.5.1) lib/thin/connection.rb:54:in `process'
thin (1.5.1) lib/thin/connection.rb:39:in `receive_data'
eventmachine (1.0.3) lib/eventmachine.rb:187:in `run_machine'
eventmachine (1.0.3) lib/eventmachine.rb:187:in `run'
thin (1.5.1) lib/thin/backends/base.rb:63:in `start'
thin (1.5.1) lib/thin/server.rb:159:in `start'
rack (1.4.5) lib/rack/handler/thin.rb:13:in `run'
rack (1.4.5) lib/rack/server.rb:268:in `start'
railties (3.2.13) lib/rails/commands/server.rb:70:in `start'
railties (3.2.13) lib/rails/commands.rb:55:in `block in <top (required)>'
railties (3.2.13) lib/rails/commands.rb:50:in `tap'
railties (3.2.13) lib/rails/commands.rb:50:in `<top (required)>'
script/rails:6:in `require'
script/rails:6:in `<main>'
答案 0 :(得分：6)
我在#rubyonrails IRC频道帮助bl0b。原来这个来自stacktrace的行：
activerecord (3.2.13) lib/active_record/associations/collection_association.rb:310:in `replace'
表示AR正在尝试分配给集合关联。我要求OP完成并尝试在update_attributes调用中一次分配一个属性。事实证明，导致这种情况的是services属性，因为记录中还有一个名为“服务”的关联。
从要更新的属性列表中删除services属性可解决此问题。