ActiveRecord: Does destroy_all execute callbacks for associated records? -


i have 4 models:

class order < webdatabase     has_many :shipments  class shipment < webdatabase     belongs_to :order     has_many :line_items, :order => "id", :dependent => :destroy  class lineitem < webdatabase     belongs_to :shipment     has_many :line_item_messages, :dependent => :destroy  class lineitemmessage < webdatabase     belongs_to :line_item

so if did @order.shipments.destroy_all, there chain of destroys @order.shipments.line_items destroyed , @order.shipments.line_items.line_item_messages destroyed because of :dependent => :destroy on each of models?

yes.

from docs (emphasis own)

destroy_all(conditions = nil)

public

destroys records matching conditions instantiating each record , calling destroy method. each object’s callbacks executed (including :dependent association options , before_destroy/after_destroy observer methods). returns collection of objects destroyed; each frozen, reflect no changes should made (since can’t persisted).

note: instantiation, callback execution, , deletion of each record can time consuming when you’re removing many records @ once. generates @ least 1 sql delete query per record (or possibly more, enforce callbacks). if want delete many rows quickly, without concern associations or callbacks, use delete_all instead.


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