README.md in dependent-auto-rails-0.2.0 vs README.md in dependent-auto-rails-0.2.1
- old
+ new
@@ -1,22 +1,24 @@
[][badges:0-gem]
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# dependent-auto-rails
-This gem provides a new `dependent` option for ActiveRecord associations, `:auto`. Using this option will automatically select between `:destroy` and `:delete` / `:delete_all` during runtime based on whether or not the associated model has any callbacks defined which would usually be executed as part of the destroy lifecycle. This is useful since `dependent: :destroy` always initialises the associated records in order to execute their callbacks regardless of whether or not there are any defined, but is often the go-to option since it is the safest. This can be expensive if there are many records to destroy.
+This gem provides a new `dependent` option for ActiveRecord associations, `:auto`. Using this option will automatically select between `:destroy` and `:delete` / `:delete_all` during runtime based on whether or not the associated model has any callbacks defined which would usually be executed as part of the destroy lifecycle.
+This is useful since `dependent: :destroy` always initialises the associated records in order to execute their callbacks regardless of whether or not there are any defined, but is often the go-to option since it is the safest. This can be expensive if there are many records to destroy.
+
It is also useful since a model's associations are rarely updated, but it's business logic can change frequently. This means that if destroy callbacks are added or removed on the associated model, the `dependent` option on the parent model's association may need to be updated to reflect this. Using `dependent: :auto` will automatically select the appropriate `dependent` option based on the current state of the model.
-If you're looking for a solution with little less magic, check out https://github.com/gregnavis/active_record_doctor's `incorrect_dependent_option` detector.
-
**NOTE**: The `:auto` option **ONLY** decides between `:destroy` and `:delete` / `:delete_all`. It does not use any of the other `dependent` options:
- `:nullify`
- `:destroy_async`
- `:restrict_with_error`
- `:restrict_with_exception`
**NOTE**: If for some reason the `:auto` option is unable to decide between `:destroy` and `:delete` / `:delete_all`, it will default to `:destroy`.
+
+**INFO**: If you're looking for a solution with a little less magic, check out the `incorrect_dependent_option` detector provided by https://github.com/gregnavis/active_record_doctor.
## Installation
Install the gem and add it to the application's Gemfile by executing: