猫鼬查询填充字段 [英] Mongoose query a populated field

问题描述

   db.History.find({'_file.project': 'someproject' )
      .populate('_file', 'name reference project')
      .sort(sortField || '-created')
      .limit(max || 64)
      .exec(this);

在这里，我正在尝试从_file参考中查找与填充字段匹配的所有文档.是似乎不起作用.这样的事情有可能吗?

Here I'm trying to find all documents which match on a populated field from the _file reference. Is doesn't seem to work. Is something like this possible at all?

我可以将项目字段复制到该对象，作为仅用于查询的解决方法，但我当然不愿意.

I could duplicate the project field to this object, as a workaround just for querying but I'd rather not of course.

推荐答案

否，find查询的conditions参数只能引用要查询的集合.

No, a find query's conditions parameter can only reference the collection being queried.

populate不是联接，它只是方便的功能，可以在主查询之后附加其他查询以从其他集合中提取关联数据.

populate is not a join, it's just a convenience function to follow up the main query with additional queries to pull in the associated data from other collections.

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