Insertion/Deletion callbacks

Rails 2

You can use

record.send(:update_without_callbacks)

or

record.send(:create_without_callbacks)

This can be used as a lightweight alternative to machinist's make or FactoryGirl's create, when you just need objects...

So you added a new callback to your model that (e.g.) caches some data when it is saved. Now you need to run that callback for the 10000 existing records in the production database. You have two options here:

1. Write a clever migration, possibly...

If you use transactional_fixtures or the database_cleaner gem with strategy :transaction, after_commit callbacks will not be fired in your tests.

Rails 5+

Rails 5 has a [fix](https://...

When an object is created / updated, various callbacks are executed in this order:

before_validation
after_validation
before_save
around_save
before_create
aro...

A while back, I had a requirement to persist a record of which email addresses were sent an email through the system. I expected to find callback support for ActionMailer, but was surprised to find that it didn't exist.

How delayed jobs can make your after_save callbacks execute before the record is saved.

There is now a solution.

Finish the remainder of the ActiveModel todo list (observers, callbacks, validations, scoping, and serialization) in addition to associations. Also wire up ActiveModel up to ActiveRecord and ActiveResource.

If you need to look at the list of methods that are called upon certain events (like before/after saving etc), do this:

Model._save_callbacks.select {|cb| cb.kind == :before}.map{ |c| c.instance_variable_get :@filter }

Rails 2

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