我遇到了一个非常奇怪的错误，只是间歇性的。我刚刚完成了从 Rails 3.0 到 Rails 3.2 的升级。3.0 应用程序一直在 Heroku 的 Bamboo 堆栈上运行，并且在升级的同时，我也在更改为更现代的 Cedar 堆栈。
Heroku 的迁移说明说使用PG Backups将数据从旧 Bamboo 应用程序迁移到新的 Cedar 应用程序。
我已经按照上述文档中的说明完成了所有工作。现在，我的应用程序大部分都可以工作。我已经测试了所有功能，检查/加载了所有页面，新的 Cedar 应用程序运行良好。
原因如下：间歇性地，该应用程序不会加载几秒钟前还在工作的页面，而是会给出 500 错误。错误是ActiveRecord::StatementInvalid: PG::Error: ERROR: relation "users" does not exist，如果您多次刷新同一页面，它就会消失并加载页面。不断刷新，最终还是会再次报错。
我读到的关于错误的所有内容都说要运行rake db:migrate，但在进行数据迁移之前，我已经在旧的 Bamboo 应用程序上完成了该操作！从 3.0 升级到 3.2 没有涉及数据库更改。此外，如果这是一个迁移问题，则该页面不应该加载。
我在下面包含了 Airbrake 的回溯。帮助表示赞赏。
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