diff options
Diffstat (limited to 'activerecord/lib/active_record/associations.rb')
-rw-r--r-- | activerecord/lib/active_record/associations.rb | 33 |
1 files changed, 26 insertions, 7 deletions
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb index 34684ad2f5..958821add6 100644 --- a/activerecord/lib/active_record/associations.rb +++ b/activerecord/lib/active_record/associations.rb @@ -1,4 +1,3 @@ -require 'active_support/core_ext/array/wrap' require 'active_support/core_ext/enumerable' require 'active_support/core_ext/module/delegation' require 'active_support/core_ext/object/blank' @@ -70,7 +69,7 @@ module ActiveRecord end end - class HasManyThroughNestedAssociationsAreReadonly < ActiveRecordError #:nodoc + class HasManyThroughNestedAssociationsAreReadonly < ActiveRecordError #:nodoc: def initialize(owner, reflection) super("Cannot modify association '#{owner.class.name}##{reflection.name}' because it goes through more than one other association.") end @@ -196,6 +195,26 @@ module ActiveRecord # * <tt>Project#categories.empty?, Project#categories.size, Project#categories, Project#categories<<(category1),</tt> # <tt>Project#categories.delete(category1)</tt> # + # === Overriding generated methods + # + # Association methods are generated in a module that is included into the model class, + # which allows you to easily override with your own methods and call the original + # generated method with +super+. For example: + # + # class Car < ActiveRecord::Base + # belongs_to :owner + # belongs_to :old_owner + # def owner=(new_owner) + # self.old_owner = self.owner + # super + # end + # end + # + # If your model class is <tt>Project</tt>, the module is + # named <tt>Project::GeneratedFeatureMethods</tt>. The GeneratedFeatureMethods module is + # included in the model class immediately after the (anonymous) generated attributes methods + # module, meaning an association will override the methods for an attribute with the same name. + # # === A word of warning # # Don't create associations that have the same name as instance methods of @@ -1078,8 +1097,8 @@ module ActiveRecord # alongside this object by calling their +destroy+ method. If set to <tt>:delete_all</tt> all associated # objects are deleted *without* calling their +destroy+ method. If set to <tt>:nullify</tt> all associated # objects' foreign keys are set to +NULL+ *without* calling their +save+ callbacks. If set to - # <tt>:restrict</tt> this object raises an <tt>ActiveRecord::DeleteRestrictionError</tt> exception and - # cannot be deleted if it has any associated objects. + # <tt>:restrict</tt> an error will be added to the object, preventing its deletion, if any associated + # objects are present. # # If using with the <tt>:through</tt> option, the association on the join model must be # a +belongs_to+, and the records which get deleted are the join records, rather than @@ -1165,7 +1184,7 @@ module ActiveRecord # has_many :subscribers, :through => :subscriptions, :source => :user # has_many :subscribers, :class_name => "Person", :finder_sql => Proc.new { # %Q{ - # SELECT DISTINCT people.* + # SELECT DISTINCT * # FROM people p, post_subscriptions ps # WHERE ps.post_id = #{id} AND ps.person_id = p.id # ORDER BY p.first_name @@ -1232,8 +1251,8 @@ module ActiveRecord # If set to <tt>:destroy</tt>, the associated object is destroyed when this object is. If set to # <tt>:delete</tt>, the associated object is deleted *without* calling its destroy method. # If set to <tt>:nullify</tt>, the associated object's foreign key is set to +NULL+. - # Also, association is assigned. If set to <tt>:restrict</tt> this object raises an - # <tt>ActiveRecord::DeleteRestrictionError</tt> exception and cannot be deleted if it has any associated object. + # If set to <tt>:restrict</tt>, an error will be added to the object, preventing its deletion, if an + # associated object is present. # [:foreign_key] # Specify the foreign key used for the association. By default this is guessed to be the name # of this class in lower-case and "_id" suffixed. So a Person class that makes a +has_one+ association |