How would you do a find on two different models and sort both in one array by created_at column

So for example ...

Lets say I have a Posts model and a News model, that are essentially the same thing (structure wise)

columns are

* title

* content

* createdat

* updatedat

The client has requested showing both news and Posts on the same page interleaved and sorted by created开发者_Go百科_at date ...

Does anyone know how I would go about doing something like this?

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(Post.all + News.all).sort_by(&:created_at)

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Just a warning, cwninja's answer will be really slow with large datasets because it requires pulling ALL of the members out of the database and then running a sort on them.

I would rarely suggest raw SQL, but in this case I can't think of a better way.