Rails ActiveRecord：是否可以组合 :include 和 :conditions 查询？
想象一下我有 wiki 文章，有很多修订。我想通过数据库使用 ActiveRecord 进行查询，该查询仅返回那些在过去 24 小时内更新过修订的文章。这样的事可能吗？
我想它会是这样的：
Articles.find_all(:include => :revisions,
:conditions => {:revision[updated_at] => 1.week.ago..Time.now.utc})
如果这不可能，是否有某种类型的原始 SQL 我可以传递给 find_by_SQL 来实现这个目的？
Imagine I have wiki Articles, with many Revisions. I'd like to do a query with ActiveRecord through the database, which only returns those Articles which have Revisions which are updated in the past 24 hours. Is such a thing possible?
I'd imagine it'd be something like:
Articles.find_all(:include => :revisions,
:conditions => {:revision[updated_at] => 1.week.ago..Time.now.utc})
If this isn't possible, is there some type of raw SQL I could pass to find_by_SQL that'd do the trick?
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如果您只需要文章而不需要立即加载所有修订版，则可以使用 :joins 代替。它使用较少的内存，因为它不会预加载每篇文章的所有修订。如果您要执行类似
article.revisions之类的操作，请使用 :include 。If you only need the article and don't need eager loading of all the revisions, you could use :joins instead. It uses less memory because it's not preloading all the revisions for each article. Use :include though if you will be doing something like
article.revisions.根据您对模型的具体命名方式，它会是这样的。
Depending on how exactly you have your models named, it's going to be something like this.