ActiveRecord :dependent confusion

I have the following AR models defined:

class Venue < ActiveRecord::Base
  has_many :events
end

class Act < ActiveRecord::Base
  has_many :events
end

class Event < ActiveRecord::Base
  belongs_to :venue
  belongs_to :act
end

What I want is if I delete a Venue or Act, any associated Events are also deleted. But if I delete an Event, the associated Venue and Act are NOT deleted. I've tried various :dependent variations, but开发者_如何转开发 nothing seems to be working.

This seems so simple. What am I missing?

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This works for me. Deleting Venue/Act deletes all events it had, while deleting an event has no effect on Venue/Act it belonged to.

class Venue < ActiveRecord::Base
  has_many :events, :dependent => :destroy
end

class Act < ActiveRecord::Base
  has_many :events, :dependent => :destroy
end

class Event < ActiveRecord::Base
  belongs_to :venue
  belongs_to :act
end

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I figured out the problem. I had to call destroy instead of delete on the parent object. The docs don't really make that clear.