ActiveRecord: Order a scope by descending value without writing SQL
Instead of this:
Image.order('images.created_at DESC')
You can write this:
Image.order(created_at: :desc)
Not only do you not have to write SQL, you also get qualified column names (created_at becomes images.created_at) for free.
Multiple order criteria
To add secondary order criteria, use a hash with multiple keys and :asc / :desc values:
Image.order(title: :asc, created_at: :desc)
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