我遇到了一个非常奇怪的错误，只是偶尔发生。我刚刚完成了从Rails 3.0升级到Rails 3.2的工作。3.0应用程序一直在Heroku的Bamboo堆栈上运行，并且与升级同时进行，我还将其更改为更现代的Cedar堆栈。
Heroku的迁移说明建议使用PG备份将数据从旧的Bamboo应用程序迁移到新的Cedar应用程序。
我按照上述文档中给出的说明做了所有事情。现在，我的应用程序大部分正常工作。我测试了所有功能，检查/加载了所有页面，新的Cedar应用程序大部分正常运行。
这里是“大多数”的原因：间歇性地，应用程序会给出500错误，而不是加载几秒钟前正常工作的页面。错误是“ActiveRecord :: StatementInvalid：PG :: Error：ERROR：关系“users”不存在”，如果您刷新同一页几次，它就会消失并重新加载页面。继续刷新，最终会再次出现错误。
我读到的有关该错误的所有内容都建议运行“rake db：migrate”，但在进行数据迁移之前，我已经在旧的Bamboo应用程序上执行了此操作！从3.0升级到3.2没有涉及任何数据库更改。另外，如果是迁移问题，则页面永远不应该加载。
下面附有Airbrake的回溯信息。感谢您的帮助。
Heroku的迁移说明建议使用PG备份将数据从旧的Bamboo应用程序迁移到新的Cedar应用程序。
我按照上述文档中给出的说明做了所有事情。现在，我的应用程序大部分正常工作。我测试了所有功能，检查/加载了所有页面，新的Cedar应用程序大部分正常运行。
这里是“大多数”的原因：间歇性地，应用程序会给出500错误，而不是加载几秒钟前正常工作的页面。错误是“ActiveRecord :: StatementInvalid：PG :: Error：ERROR：关系“users”不存在”，如果您刷新同一页几次，它就会消失并重新加载页面。继续刷新，最终会再次出现错误。
我读到的有关该错误的所有内容都建议运行“rake db：migrate”，但在进行数据迁移之前，我已经在旧的Bamboo应用程序上执行了此操作！从3.0升级到3.2没有涉及任何数据库更改。另外，如果是迁移问题，则页面永远不应该加载。
下面附有Airbrake的回溯信息。感谢您的帮助。
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vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/relation.rb:159:in `to_a'
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