如何在 ActiveRecord 的 where 中有条件地调用属性？

Question

我有一段代码看起来像：

foreign_object = (some_test) ? nil : <some foreign_object>

Document.where(foreign_id: foreign_object, status: "Working", ... )

如果foreign_object为nil，它只会找到foreign_id = NULL的文档。有没有办法有条件地将 foreign_id 放入？我基本上想写：

Document.where(foreign_id: foreign_object if foreign_object, status: "Working", ...)

Answer 1

遇到这种情况我会这样做：

 documents = Document.where(status: 'working')
 documents = documents.where(foreign_id: foreign_object) if foreign_object