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rails / activerecord / lib / active_record / associations.rb
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db045dbb » dhh 2004-11-23 Initial 1 module ActiveRecord
fed7d334 » dhh 2006-03-27 Fixed documentation 2 class HasManyThroughAssociationNotFoundError < ActiveRecordError #:nodoc:
291adbd3 » technoweenie 2006-07-19 fix association exception m... 3 def initialize(owner_class_name, reflection)
4 super("Could not find the association #{reflection.options[:through].inspect} in model #{owner_class_name}")
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 5 end
6 end
7
fed7d334 » dhh 2006-03-27 Fixed documentation 8 class HasManyThroughAssociationPolymorphicError < ActiveRecordError #:nodoc:
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 9 def initialize(owner_class_name, reflection, source_reflection)
291adbd3 » technoweenie 2006-07-19 fix association exception m... 10 super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' on the polymorphic object '#{source_reflection.class_name}##{source_reflection.name}'.")
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 11 end
12 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 13
e3dab67c » technoweenie 2007-03-12 Allow a polymorphic :source... 14 class HasManyThroughAssociationPointlessSourceTypeError < ActiveRecordError #:nodoc:
15 def initialize(owner_class_name, reflection, source_reflection)
16 super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' with a :source_type option if the '#{reflection.through_reflection.class_name}##{source_reflection.name}' is not polymorphic. Try removing :source_type on your association.")
17 end
18 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 19
fed7d334 » dhh 2006-03-27 Fixed documentation 20 class HasManyThroughSourceAssociationNotFoundError < ActiveRecordError #:nodoc:
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 21 def initialize(reflection)
291adbd3 » technoweenie 2006-07-19 fix association exception m... 22 through_reflection = reflection.through_reflection
23 source_reflection_names = reflection.source_reflection_names
24 source_associations = reflection.through_reflection.klass.reflect_on_all_associations.collect { |a| a.name.inspect }
6de83562 » dhh 2009-02-27 Force all internal calls to... 25 super("Could not find the source association(s) #{source_reflection_names.collect(&:inspect).to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence(:two_words_connector => ' or ', :last_word_connector => ', or ', :locale => :en)}?")
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 26 end
27 end
28
0aa0c84c » dhh 2007-01-26 Nodoc the irrelevant (from ... 29 class HasManyThroughSourceAssociationMacroError < ActiveRecordError #:nodoc:
4d232025 » technoweenie 2006-04-05 Added descriptive error mes... 30 def initialize(reflection)
291adbd3 » technoweenie 2006-07-19 fix association exception m... 31 through_reflection = reflection.through_reflection
32 source_reflection = reflection.source_reflection
33 super("Invalid source reflection macro :#{source_reflection.macro}#{" :through" if source_reflection.options[:through]} for has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}. Use :source to specify the source reflection.")
4d232025 » technoweenie 2006-04-05 Added descriptive error mes... 34 end
35 end
36
f6b12c11 » lifo 2008-04-05 Refactor HasManyThroughAsso... 37 class HasManyThroughCantAssociateThroughHasManyReflection < ActiveRecordError #:nodoc:
38 def initialize(owner, reflection)
39 super("Cannot modify association '#{owner.class.name}##{reflection.name}' because the source reflection class '#{reflection.source_reflection.class_name}' is associated to '#{reflection.through_reflection.class_name}' via :#{reflection.source_reflection.macro}.")
40 end
41 end
0da426be » jeremy 2006-08-18 Add records to has_many :th... 42 class HasManyThroughCantAssociateNewRecords < ActiveRecordError #:nodoc:
43 def initialize(owner, reflection)
44 super("Cannot associate new records through '#{owner.class.name}##{reflection.name}' on '#{reflection.source_reflection.class_name rescue nil}##{reflection.source_reflection.name rescue nil}'. Both records must have an id in order to create the has_many :through record associating them.")
45 end
46 end
47
4b639904 » jeremy 2007-10-27 Fix has_many :through delet... 48 class HasManyThroughCantDissociateNewRecords < ActiveRecordError #:nodoc:
49 def initialize(owner, reflection)
50 super("Cannot dissociate new records through '#{owner.class.name}##{reflection.name}' on '#{reflection.source_reflection.class_name rescue nil}##{reflection.source_reflection.name rescue nil}'. Both records must have an id in order to delete the has_many :through record associating them.")
51 end
52 end
53
fed7d334 » dhh 2006-03-27 Fixed documentation 54 class EagerLoadPolymorphicError < ActiveRecordError #:nodoc:
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 55 def initialize(reflection)
291adbd3 » technoweenie 2006-07-19 fix association exception m... 56 super("Can not eagerly load the polymorphic association #{reflection.name.inspect}")
57af961a » technoweenie 2006-03-18 Raise error when trying to ... 57 end
58 end
59
c61b10b6 » technoweenie 2006-04-24 Raise error when trying to ... 60 class ReadOnlyAssociation < ActiveRecordError #:nodoc:
61 def initialize(reflection)
291adbd3 » technoweenie 2006-07-19 fix association exception m... 62 super("Can not add to a has_many :through association. Try adding to #{reflection.through_reflection.name.inspect}.")
c61b10b6 » technoweenie 2006-04-24 Raise error when trying to ... 63 end
64 end
65
6e754551 » lifo 2008-07-28 Merge docrails changes 66 # See ActiveRecord::Associations::ClassMethods for documentation.
db045dbb » dhh 2004-11-23 Initial 67 module Associations # :nodoc:
7254d237 » josh 2008-11-24 Autoload ActiveRecord files 68 # These classes will be loaded when associatoins are created.
69 # So there is no need to eager load them.
70 autoload :AssociationCollection, 'active_record/associations/association_collection'
71 autoload :AssociationProxy, 'active_record/associations/association_proxy'
72 autoload :BelongsToAssociation, 'active_record/associations/belongs_to_association'
73 autoload :BelongsToPolymorphicAssociation, 'active_record/associations/belongs_to_polymorphic_association'
74 autoload :HasAndBelongsToManyAssociation, 'active_record/associations/has_and_belongs_to_many_association'
75 autoload :HasManyAssociation, 'active_record/associations/has_many_association'
76 autoload :HasManyThroughAssociation, 'active_record/associations/has_many_through_association'
77 autoload :HasOneAssociation, 'active_record/associations/has_one_association'
78 autoload :HasOneThroughAssociation, 'active_record/associations/has_one_through_association'
79
61864909 » Marcel Molina 2006-04-29 Replace Ruby's deprecated a... 80 def self.included(base)
7c8d2f28 » dhh 2005-04-02 Removed broken attempt to D... 81 base.extend(ClassMethods)
82 end
83
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 84 # Clears out the association cache
4b229d10 » dhh 2004-12-22 Added Base#clear_associatio... 85 def clear_association_cache #:nodoc:
86 self.class.reflect_on_all_associations.to_a.each do |assoc|
87 instance_variable_set "@#{assoc.name}", nil
85fbb22f » dhh 2006-09-05 Backed out of new_record? t... 88 end unless self.new_record?
4b229d10 » dhh 2004-12-22 Added Base#clear_associatio... 89 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 90
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 91 private
92 # Gets the specified association instance if it responds to :loaded?, nil otherwise.
93 def association_instance_get(name)
94 association = instance_variable_get("@#{name}")
95 association if association.respond_to?(:loaded?)
96 end
97
98 # Set the specified association instance.
99 def association_instance_set(name, association)
100 instance_variable_set("@#{name}", association)
101 end
102
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 103 # Associations are a set of macro-like class methods for tying objects together through foreign keys. They express relationships like
104 # "Project has one Project Manager" or "Project belongs to a Portfolio". Each macro adds a number of methods to the class which are
105 # specialized according to the collection or association symbol and the options hash. It works much the same way as Ruby's own <tt>attr*</tt>
db045dbb » dhh 2004-11-23 Initial 106 # methods. Example:
107 #
108 # class Project < ActiveRecord::Base
109 # belongs_to :portfolio
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 110 # has_one :project_manager
db045dbb » dhh 2004-11-23 Initial 111 # has_many :milestones
112 # has_and_belongs_to_many :categories
113 # end
114 #
115 # The project class now has the following methods (and more) to ease the traversal and manipulation of its relationships:
823554ea » dhh 2005-01-15 Added support for associati... 116 # * <tt>Project#portfolio, Project#portfolio=(portfolio), Project#portfolio.nil?</tt>
db045dbb » dhh 2004-11-23 Initial 117 # * <tt>Project#project_manager, Project#project_manager=(project_manager), Project#project_manager.nil?,</tt>
118 # * <tt>Project#milestones.empty?, Project#milestones.size, Project#milestones, Project#milestones<<(milestone),</tt>
7aa9eed8 » jeremy 2006-09-01 Deprecation: update docs. C... 119 # <tt>Project#milestones.delete(milestone), Project#milestones.find(milestone_id), Project#milestones.find(:all, options),</tt>
db045dbb » dhh 2004-11-23 Initial 120 # <tt>Project#milestones.build, Project#milestones.create</tt>
121 # * <tt>Project#categories.empty?, Project#categories.size, Project#categories, Project#categories<<(category1),</tt>
122 # <tt>Project#categories.delete(category1)</tt>
123 #
7288fd3e » jeremy 2007-05-18 Docs: warn that association... 124 # === A word of warning
125 #
126 # Don't create associations that have the same name as instance methods of ActiveRecord::Base. Since the association
127 # adds a method with that name to its model, it will override the inherited method and break things.
dc4eec11 » lifo 2008-05-09 Merge docrails: 128 # For instance, +attributes+ and +connection+ would be bad choices for association names.
7288fd3e » jeremy 2007-05-18 Docs: warn that association... 129 #
ff6d2aae » jeremy 2007-05-30 Quickref for association me... 130 # == Auto-generated methods
db045dbb » dhh 2004-11-23 Initial 131 #
c23c9bd1 » technoweenie 2008-03-21 Allow association scoping f... 132 # === Singular associations (one-to-one)
ff6d2aae » jeremy 2007-05-30 Quickref for association me... 133 # | | belongs_to |
134 # generated methods | belongs_to | :polymorphic | has_one
135 # ----------------------------------+------------+--------------+---------
53cd102b » lifo 2009-02-24 Merge with docrails 136 # other | X | X | X
137 # other=(other) | X | X | X
138 # build_other(attributes={}) | X | | X
139 # create_other(attributes={}) | X | | X
140 # other.create!(attributes={}) | | | X
ff6d2aae » jeremy 2007-05-30 Quickref for association me... 141 #
142 # ===Collection associations (one-to-many / many-to-many)
143 # | | | has_many
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 144 # generated methods | habtm | has_many | :through
ff6d2aae » jeremy 2007-05-30 Quickref for association me... 145 # ----------------------------------+-------+----------+----------
53cd102b » lifo 2009-02-24 Merge with docrails 146 # others | X | X | X
147 # others=(other,other,...) | X | X | X
148 # other_ids | X | X | X
149 # other_ids=(id,id,...) | X | X | X
150 # others<< | X | X | X
151 # others.push | X | X | X
152 # others.concat | X | X | X
153 # others.build(attributes={}) | X | X | X
154 # others.create(attributes={}) | X | X | X
155 # others.create!(attributes={}) | X | X | X
156 # others.size | X | X | X
157 # others.length | X | X | X
158 # others.count | X | X | X
159 # others.sum(args*,&block) | X | X | X
160 # others.empty? | X | X | X
161 # others.clear | X | X | X
162 # others.delete(other,other,...) | X | X | X
163 # others.delete_all | X | X |
164 # others.destroy_all | X | X | X
165 # others.find(*args) | X | X | X
166 # others.find_first | X | |
167 # others.exists? | X | X | X
168 # others.uniq | X | X | X
169 # others.reset | X | X | X
db045dbb » dhh 2004-11-23 Initial 170 #
51d840e2 » NZKoz 2007-01-14 Improve association documen... 171 # == Cardinality and associations
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 172 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 173 # Active Record associations can be used to describe one-to-one, one-to-many and many-to-many
aa4af60a » lifo 2008-04-04 Improve documentation. 174 # relationships between models. Each model uses an association to describe its role in
175 # the relation. The +belongs_to+ association is always used in the model that has
8296c680 » technoweenie 2007-01-22 Remove useless code in #att... 176 # the foreign key.
51d840e2 » NZKoz 2007-01-14 Improve association documen... 177 #
178 # === One-to-one
179 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 180 # Use +has_one+ in the base, and +belongs_to+ in the associated model.
51d840e2 » NZKoz 2007-01-14 Improve association documen... 181 #
182 # class Employee < ActiveRecord::Base
183 # has_one :office
184 # end
185 # class Office < ActiveRecord::Base
186 # belongs_to :employee # foreign key - employee_id
187 # end
188 #
189 # === One-to-many
190 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 191 # Use +has_many+ in the base, and +belongs_to+ in the associated model.
51d840e2 » NZKoz 2007-01-14 Improve association documen... 192 #
193 # class Manager < ActiveRecord::Base
194 # has_many :employees
195 # end
196 # class Employee < ActiveRecord::Base
8296c680 » technoweenie 2007-01-22 Remove useless code in #att... 197 # belongs_to :manager # foreign key - manager_id
51d840e2 » NZKoz 2007-01-14 Improve association documen... 198 # end
199 #
200 # === Many-to-many
201 #
202 # There are two ways to build a many-to-many relationship.
203 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 204 # The first way uses a +has_many+ association with the <tt>:through</tt> option and a join model, so
51d840e2 » NZKoz 2007-01-14 Improve association documen... 205 # there are two stages of associations.
206 #
207 # class Assignment < ActiveRecord::Base
208 # belongs_to :programmer # foreign key - programmer_id
209 # belongs_to :project # foreign key - project_id
210 # end
211 # class Programmer < ActiveRecord::Base
212 # has_many :assignments
213 # has_many :projects, :through => :assignments
214 # end
215 # class Project < ActiveRecord::Base
216 # has_many :assignments
217 # has_many :programmers, :through => :assignments
218 # end
219 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 220 # For the second way, use +has_and_belongs_to_many+ in both models. This requires a join table
51d840e2 » NZKoz 2007-01-14 Improve association documen... 221 # that has no corresponding model or primary key.
222 #
223 # class Programmer < ActiveRecord::Base
224 # has_and_belongs_to_many :projects # foreign keys in the join table
225 # end
226 # class Project < ActiveRecord::Base
227 # has_and_belongs_to_many :programmers # foreign keys in the join table
228 # end
229 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 230 # Choosing which way to build a many-to-many relationship is not always simple.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 231 # If you need to work with the relationship model as its own entity,
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 232 # use <tt>has_many :through</tt>. Use +has_and_belongs_to_many+ when working with legacy schemas or when
51d840e2 » NZKoz 2007-01-14 Improve association documen... 233 # you never work directly with the relationship itself.
234 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 235 # == Is it a +belongs_to+ or +has_one+ association?
db045dbb » dhh 2004-11-23 Initial 236 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 237 # Both express a 1-1 relationship. The difference is mostly where to place the foreign key, which goes on the table for the class
238 # declaring the +belongs_to+ relationship. Example:
db045dbb » dhh 2004-11-23 Initial 239 #
69d8ca4c » jeremy 2006-07-07 Clearer has_one/belongs_to ... 240 # class User < ActiveRecord::Base
241 # # I reference an account.
242 # belongs_to :account
db045dbb » dhh 2004-11-23 Initial 243 # end
244 #
69d8ca4c » jeremy 2006-07-07 Clearer has_one/belongs_to ... 245 # class Account < ActiveRecord::Base
246 # # One user references me.
247 # has_one :user
db045dbb » dhh 2004-11-23 Initial 248 # end
249 #
250 # The tables for these classes could look something like:
251 #
69d8ca4c » jeremy 2006-07-07 Clearer has_one/belongs_to ... 252 # CREATE TABLE users (
db045dbb » dhh 2004-11-23 Initial 253 # id int(11) NOT NULL auto_increment,
69d8ca4c » jeremy 2006-07-07 Clearer has_one/belongs_to ... 254 # account_id int(11) default NULL,
255 # name varchar default NULL,
db045dbb » dhh 2004-11-23 Initial 256 # PRIMARY KEY (id)
257 # )
258 #
69d8ca4c » jeremy 2006-07-07 Clearer has_one/belongs_to ... 259 # CREATE TABLE accounts (
db045dbb » dhh 2004-11-23 Initial 260 # id int(11) NOT NULL auto_increment,
261 # name varchar default NULL,
262 # PRIMARY KEY (id)
263 # )
264 #
823554ea » dhh 2005-01-15 Added support for associati... 265 # == Unsaved objects and associations
266 #
7143d801 » Marcel Molina 2007-11-07 Smattering of grammatical f... 267 # You can manipulate objects and associations before they are saved to the database, but there is some special behavior you should be
823554ea » dhh 2005-01-15 Added support for associati... 268 # aware of, mostly involving the saving of associated objects.
269 #
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 270 # Unless you enable the :autosave option on a <tt>has_one</tt>, <tt>belongs_to</tt>,
271 # <tt>has_many</tt>, or <tt>has_and_belongs_to_many</tt> association,
272 # in which case the members are always saved.
273 #
823554ea » dhh 2005-01-15 Added support for associati... 274 # === One-to-one associations
275 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 276 # * Assigning an object to a +has_one+ association automatically saves that object and the object being replaced (if there is one), in
277 # order to update their primary keys - except if the parent object is unsaved (<tt>new_record? == true</tt>).
278 # * If either of these saves fail (due to one of the objects being invalid) the assignment statement returns +false+ and the assignment
823554ea » dhh 2005-01-15 Added support for associati... 279 # is cancelled.
dc4eec11 » lifo 2008-05-09 Merge docrails: 280 # * If you wish to assign an object to a +has_one+ association without saving it, use the <tt>association.build</tt> method (documented below).
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 281 # * Assigning an object to a +belongs_to+ association does not save the object, since the foreign key field belongs on the parent. It
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 282 # does not save the parent either.
823554ea » dhh 2005-01-15 Added support for associati... 283 #
284 # === Collections
285 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 286 # * Adding an object to a collection (+has_many+ or +has_and_belongs_to_many+) automatically saves that object, except if the parent object
823554ea » dhh 2005-01-15 Added support for associati... 287 # (the owner of the collection) is not yet stored in the database.
dc4eec11 » lifo 2008-05-09 Merge docrails: 288 # * If saving any of the objects being added to a collection (via <tt>push</tt> or similar) fails, then <tt>push</tt> returns +false+.
289 # * You can add an object to a collection without automatically saving it by using the <tt>collection.build</tt> method (documented below).
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 290 # * All unsaved (<tt>new_record? == true</tt>) members of the collection are automatically saved when the parent is saved.
823554ea » dhh 2005-01-15 Added support for associati... 291 #
17f7f8a0 » dhh 2005-07-06 Made documentation ready fo... 292 # === Association callbacks
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 293 #
2af36bbb » dhh 2007-12-05 Fix typos (closes #10378) 294 # Similar to the normal callbacks that hook into the lifecycle of an Active Record object, you can also define callbacks that get
7143d801 » Marcel Molina 2007-11-07 Smattering of grammatical f... 295 # triggered when you add an object to or remove an object from an association collection. Example:
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 296 #
297 # class Project
298 # has_and_belongs_to_many :developers, :after_add => :evaluate_velocity
299 #
300 # def evaluate_velocity(developer)
301 # ...
302 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 303 # end
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 304 #
305 # It's possible to stack callbacks by passing them as an array. Example:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 306 #
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 307 # class Project
17f7f8a0 » dhh 2005-07-06 Made documentation ready fo... 308 # has_and_belongs_to_many :developers, :after_add => [:evaluate_velocity, Proc.new { |p, d| p.shipping_date = Time.now}]
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 309 # end
310 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 311 # Possible callbacks are: +before_add+, +after_add+, +before_remove+ and +after_remove+.
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 312 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 313 # Should any of the +before_add+ callbacks throw an exception, the object does not get added to the collection. Same with
314 # the +before_remove+ callbacks; if an exception is thrown the object doesn't get removed.
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 315 #
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 316 # === Association extensions
317 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 318 # The proxy objects that control the access to associations can be extended through anonymous modules. This is especially
3c01e01d » Marcel Molina 2005-12-19 Fix typo in association doc... 319 # beneficial for adding new finders, creators, and other factory-type methods that are only used as part of this association.
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 320 # Example:
321 #
322 # class Account < ActiveRecord::Base
c8dd66fd » dhh 2005-11-06 Made association extensions... 323 # has_many :people do
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 324 # def find_or_create_by_name(name)
e5d9ad3e » dhh 2005-12-12 Added option inheritance fo... 325 # first_name, last_name = name.split(" ", 2)
da7752e5 » dhh 2005-11-06 Sharper example 326 # find_or_create_by_first_name_and_last_name(first_name, last_name)
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 327 # end
c8dd66fd » dhh 2005-11-06 Made association extensions... 328 # end
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 329 # end
330 #
331 # person = Account.find(:first).people.find_or_create_by_name("David Heinemeier Hansson")
332 # person.first_name # => "David"
333 # person.last_name # => "Heinemeier Hansson"
334 #
c8dd66fd » dhh 2005-11-06 Made association extensions... 335 # If you need to share the same extensions between many associations, you can use a named extension module. Example:
336 #
337 # module FindOrCreateByNameExtension
338 # def find_or_create_by_name(name)
e5d9ad3e » dhh 2005-12-12 Added option inheritance fo... 339 # first_name, last_name = name.split(" ", 2)
da7752e5 » dhh 2005-11-06 Sharper example 340 # find_or_create_by_first_name_and_last_name(first_name, last_name)
c8dd66fd » dhh 2005-11-06 Made association extensions... 341 # end
342 # end
343 #
344 # class Account < ActiveRecord::Base
345 # has_many :people, :extend => FindOrCreateByNameExtension
346 # end
347 #
348 # class Company < ActiveRecord::Base
349 # has_many :people, :extend => FindOrCreateByNameExtension
350 # end
8c512a1c » dhh 2005-11-03 Added extension capabilitie... 351 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 352 # If you need to use multiple named extension modules, you can specify an array of modules with the <tt>:extend</tt> option.
7e76740d » technoweenie 2006-04-10 Allow multiple association... 353 # In the case of name conflicts between methods in the modules, methods in modules later in the array supercede
354 # those earlier in the array. Example:
355 #
356 # class Account < ActiveRecord::Base
357 # has_many :people, :extend => [FindOrCreateByNameExtension, FindRecentExtension]
358 # end
359 #
ea51d72e » technoweenie 2006-05-28 Provide Association Extensi... 360 # Some extensions can only be made to work with knowledge of the association proxy's internals.
361 # Extensions can access relevant state using accessors on the association proxy:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 362 #
ea51d72e » technoweenie 2006-05-28 Provide Association Extensi... 363 # * +proxy_owner+ - Returns the object the association is part of.
364 # * +proxy_reflection+ - Returns the reflection object that describes the association.
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 365 # * +proxy_target+ - Returns the associated object for +belongs_to+ and +has_one+, or the collection of associated objects for +has_many+ and +has_and_belongs_to_many+.
ea51d72e » technoweenie 2006-05-28 Provide Association Extensi... 366 #
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 367 # === Association Join Models
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 368 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 369 # Has Many associations can be configured with the <tt>:through</tt> option to use an explicit join model to retrieve the data. This
370 # operates similarly to a +has_and_belongs_to_many+ association. The advantage is that you're able to add validations,
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 371 # callbacks, and extra attributes on the join model. Consider the following schema:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 372 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 373 # class Author < ActiveRecord::Base
374 # has_many :authorships
375 # has_many :books, :through => :authorships
376 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 377 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 378 # class Authorship < ActiveRecord::Base
379 # belongs_to :author
380 # belongs_to :book
381 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 382 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 383 # @author = Author.find :first
384 # @author.authorships.collect { |a| a.book } # selects all books that the author's authorships belong to.
385 # @author.books # selects all books by using the Authorship join model
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 386 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 387 # You can also go through a +has_many+ association on the join model:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 388 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 389 # class Firm < ActiveRecord::Base
390 # has_many :clients
391 # has_many :invoices, :through => :clients
392 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 393 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 394 # class Client < ActiveRecord::Base
395 # belongs_to :firm
396 # has_many :invoices
397 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 398 #
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 399 # class Invoice < ActiveRecord::Base
400 # belongs_to :client
401 # end
402 #
403 # @firm = Firm.find :first
404 # @firm.clients.collect { |c| c.invoices }.flatten # select all invoices for all clients of the firm
405 # @firm.invoices # selects all invoices by going through the Client join model.
406 #
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 407 # === Polymorphic Associations
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 408 #
409 # Polymorphic associations on models are not restricted on what types of models they can be associated with. Rather, they
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 410 # specify an interface that a +has_many+ association must adhere to.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 411 #
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 412 # class Asset < ActiveRecord::Base
413 # belongs_to :attachable, :polymorphic => true
414 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 415 #
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 416 # class Post < ActiveRecord::Base
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 417 # has_many :assets, :as => :attachable # The :as option specifies the polymorphic interface to use.
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 418 # end
419 #
420 # @asset.attachable = @post
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 421 #
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 422 # This works by using a type column in addition to a foreign key to specify the associated record. In the Asset example, you'd need
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 423 # an +attachable_id+ integer column and an +attachable_type+ string column.
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 424 #
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 425 # Using polymorphic associations in combination with single table inheritance (STI) is a little tricky. In order
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 426 # for the associations to work as expected, ensure that you store the base model for the STI models in the
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 427 # type column of the polymorphic association. To continue with the asset example above, suppose there are guest posts
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 428 # and member posts that use the posts table for STI. In this case, there must be a +type+ column in the posts table.
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 429 #
430 # class Asset < ActiveRecord::Base
431 # belongs_to :attachable, :polymorphic => true
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 432 #
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 433 # def attachable_type=(sType)
434 # super(sType.to_s.classify.constantize.base_class.to_s)
435 # end
436 # end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 437 #
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 438 # class Post < ActiveRecord::Base
439 # # because we store "Post" in attachable_type now :dependent => :destroy will work
440 # has_many :assets, :as => :attachable, :dependent => :destroy
441 # end
442 #
aa9ed408 » Marcel Molina 2007-12-05 Fix typo in documentation f... 443 # class GuestPost < Post
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 444 # end
445 #
aa9ed408 » Marcel Molina 2007-12-05 Fix typo in documentation f... 446 # class MemberPost < Post
fc7fd4c5 » dhh 2006-10-08 Docfix (closes #6040) 447 # end
448 #
db045dbb » dhh 2004-11-23 Initial 449 # == Caching
450 #
451 # All of the methods are built on a simple caching principle that will keep the result of the last query around unless specifically
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 452 # instructed not to. The cache is even shared across methods to make it even cheaper to use the macro-added methods without
db045dbb » dhh 2004-11-23 Initial 453 # worrying too much about performance at the first go. Example:
454 #
455 # project.milestones # fetches milestones from the database
456 # project.milestones.size # uses the milestone cache
457 # project.milestones.empty? # uses the milestone cache
458 # project.milestones(true).size # fetches milestones from the database
459 # project.milestones # uses the milestone cache
460 #
515886a5 » dhh 2005-04-18 Added documentation for new... 461 # == Eager loading of associations
462 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 463 # Eager loading is a way to find objects of a certain class and a number of named associations. This is
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 464 # one of the easiest ways of to prevent the dreaded 1+N problem in which fetching 100 posts that each need to display their author
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 465 # triggers 101 database queries. Through the use of eager loading, the 101 queries can be reduced to 2. Example:
515886a5 » dhh 2005-04-18 Added documentation for new... 466 #
467 # class Post < ActiveRecord::Base
468 # belongs_to :author
469 # has_many :comments
470 # end
471 #
472 # Consider the following loop using the class above:
473 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 474 # for post in Post.all
515886a5 » dhh 2005-04-18 Added documentation for new... 475 # puts "Post: " + post.title
476 # puts "Written by: " + post.author.name
477 # puts "Last comment on: " + post.comments.first.created_on
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 478 # end
515886a5 » dhh 2005-04-18 Added documentation for new... 479 #
480 # To iterate over these one hundred posts, we'll generate 201 database queries. Let's first just optimize it for retrieving the author:
481 #
4e2f7bec » dhh 2005-04-19 Added documentation about :... 482 # for post in Post.find(:all, :include => :author)
515886a5 » dhh 2005-04-18 Added documentation for new... 483 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 484 # This references the name of the +belongs_to+ association that also used the <tt>:author</tt> symbol. After loading the posts, find
485 # will collect the +author_id+ from each one and load all the referenced authors with one query. Doing so will cut down the number of queries from 201 to 102.
515886a5 » dhh 2005-04-18 Added documentation for new... 486 #
487 # We can improve upon the situation further by referencing both associations in the finder with:
488 #
4e2f7bec » dhh 2005-04-19 Added documentation about :... 489 # for post in Post.find(:all, :include => [ :author, :comments ])
515886a5 » dhh 2005-04-18 Added documentation for new... 490 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 491 # This will load all comments with a single query. This reduces the total number of queries to 3. More generally the number of queries
492 # will be 1 plus the number of associations named (except if some of the associations are polymorphic +belongs_to+ - see below).
5b414190 » jeremy 2007-05-19 Document deep eager include... 493 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 494 # To include a deep hierarchy of associations, use a hash:
5b414190 » jeremy 2007-05-19 Document deep eager include... 495 #
496 # for post in Post.find(:all, :include => [ :author, { :comments => { :author => :gravatar } } ])
497 #
498 # That'll grab not only all the comments but all their authors and gravatar pictures. You can mix and match
499 # symbols, arrays and hashes in any combination to describe the associations you want to load.
500 #
501 # All of this power shouldn't fool you into thinking that you can pull out huge amounts of data with no performance penalty just because you've reduced
a8eea0b0 » dhh 2005-10-26 Fix docs (closes #2491) 502 # the number of queries. The database still needs to send all the data to Active Record and it still needs to be processed. So it's no
503 # catch-all for performance problems, but it's a great way to cut down on the number of queries in a situation as the one described above.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 504 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 505 # Since only one table is loaded at a time, conditions or orders cannot reference tables other than the main one. If this is the case
506 # Active Record falls back to the previously used LEFT OUTER JOIN based strategy. For example
507 #
508 # Post.find(:all, :include => [ :author, :comments ], :conditions => ['comments.approved = ?', true])
515886a5 » dhh 2005-04-18 Added documentation for new... 509 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 510 # will result in a single SQL query with joins along the lines of: <tt>LEFT OUTER JOIN comments ON comments.post_id = posts.id</tt> and
511 # <tt>LEFT OUTER JOIN authors ON authors.id = posts.author_id</tt>. Note that using conditions like this can have unintended consequences.
512 # In the above example posts with no approved comments are not returned at all, because the conditions apply to the SQL statement as a whole
513 # and not just to the association. You must disambiguate column references for this fallback to happen, for example
514 # <tt>:order => "author.name DESC"</tt> will work but <tt>:order => "name DESC"</tt> will not.
515 #
516 # If you do want eagerload only some members of an association it is usually more natural to <tt>:include</tt> an association
517 # which has conditions defined on it:
518 #
519 # class Post < ActiveRecord::Base
520 # has_many :approved_comments, :class_name => 'Comment', :conditions => ['approved = ?', true]
521 # end
522 #
523 # Post.find(:all, :include => :approved_comments)
524 #
525 # will load posts and eager load the +approved_comments+ association, which contains only those comments that have been approved.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 526 #
dc37fdc4 » lifo 2008-11-02 Merge docrails. Remove unne... 527 # If you eager load an association with a specified <tt>:limit</tt> option, it will be ignored, returning all the associated objects:
528 #
529 # class Picture < ActiveRecord::Base
530 # has_many :most_recent_comments, :class_name => 'Comment', :order => 'id DESC', :limit => 10
531 # end
532 #
533 # Picture.find(:first, :include => :most_recent_comments).most_recent_comments # => returns all associated comments.
534 #
78704946 » technoweenie 2006-10-11 Restore eager condition int... 535 # When eager loaded, conditions are interpolated in the context of the model class, not the model instance. Conditions are lazily interpolated
536 # before the actual model exists.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 537 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 538 # Eager loading is supported with polymorphic associations.
752f633b » jeremy 2008-01-04 Document that eager loading... 539 #
540 # class Address < ActiveRecord::Base
541 # belongs_to :addressable, :polymorphic => true
542 # end
543 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 544 # A call that tries to eager load the addressable model
752f633b » jeremy 2008-01-04 Document that eager loading... 545 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 546 # Address.find(:all, :include => :addressable)
b2fa70a8 » Marcel Molina 2008-01-23 Indicate in documentation t... 547 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 548 # will execute one query to load the addresses and load the addressables with one query per addressable type.
549 # For example if all the addressables are either of class Person or Company then a total of 3 queries will be executed. The list of
550 # addressable types to load is determined on the back of the addresses loaded. This is not supported if Active Record has to fallback
551 # to the previous implementation of eager loading and will raise ActiveRecord::EagerLoadPolymorphicError. The reason is that the parent
552 # model's type is a column value so its corresponding table name cannot be put in the +FROM+/+JOIN+ clauses of that query.
752f633b » jeremy 2008-01-04 Document that eager loading... 553 #
ed10f873 » technoweenie 2006-03-22 STI associations are now al... 554 # == Table Aliasing
555 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 556 # Active Record uses table aliasing in the case that a table is referenced multiple times in a join. If a table is referenced only once,
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 557 # the standard table name is used. The second time, the table is aliased as <tt>#{reflection_name}_#{parent_table_name}</tt>. Indexes are appended
ed10f873 » technoweenie 2006-03-22 STI associations are now al... 558 # for any more successive uses of the table name.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 559 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 560 # Post.find :all, :joins => :comments
561 # # => SELECT ... FROM posts INNER JOIN comments ON ...
562 # Post.find :all, :joins => :special_comments # STI
563 # # => SELECT ... FROM posts INNER JOIN comments ON ... AND comments.type = 'SpecialComment'
564 # Post.find :all, :joins => [:comments, :special_comments] # special_comments is the reflection name, posts is the parent table name
565 # # => SELECT ... FROM posts INNER JOIN comments ON ... INNER JOIN comments special_comments_posts
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 566 #
ed10f873 » technoweenie 2006-03-22 STI associations are now al... 567 # Acts as tree example:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 568 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 569 # TreeMixin.find :all, :joins => :children
570 # # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
571 # TreeMixin.find :all, :joins => {:children => :parent}
572 # # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
573 # INNER JOIN parents_mixins ...
574 # TreeMixin.find :all, :joins => {:children => {:parent => :children}}
575 # # => SELECT ... FROM mixins INNER JOIN mixins childrens_mixins ...
576 # INNER JOIN parents_mixins ...
577 # INNER JOIN mixins childrens_mixins_2
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 578 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 579 # Has and Belongs to Many join tables use the same idea, but add a <tt>_join</tt> suffix:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 580 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 581 # Post.find :all, :joins => :categories
582 # # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
583 # Post.find :all, :joins => {:categories => :posts}
584 # # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
585 # INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
586 # Post.find :all, :joins => {:categories => {:posts => :categories}}
587 # # => SELECT ... FROM posts INNER JOIN categories_posts ... INNER JOIN categories ...
588 # INNER JOIN categories_posts posts_categories_join INNER JOIN posts posts_categories
589 # INNER JOIN categories_posts categories_posts_join INNER JOIN categories categories_posts_2
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 590 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 591 # If you wish to specify your own custom joins using a <tt>:joins</tt> option, those table names will take precedence over the eager associations:
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 592 #
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 593 # Post.find :all, :joins => :comments, :joins => "inner join comments ..."
594 # # => SELECT ... FROM posts INNER JOIN comments_posts ON ... INNER JOIN comments ...
595 # Post.find :all, :joins => [:comments, :special_comments], :joins => "inner join comments ..."
596 # # => SELECT ... FROM posts INNER JOIN comments comments_posts ON ...
597 # INNER JOIN comments special_comments_posts ...
ed10f873 » technoweenie 2006-03-22 STI associations are now al... 598 # INNER JOIN comments ...
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 599 #
ed10f873 » technoweenie 2006-03-22 STI associations are now al... 600 # Table aliases are automatically truncated according to the maximum length of table identifiers according to the specific database.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 601 #
db045dbb » dhh 2004-11-23 Initial 602 # == Modules
603 #
604 # By default, associations will look for objects within the current module scope. Consider:
605 #
606 # module MyApplication
607 # module Business
608 # class Firm < ActiveRecord::Base
609 # has_many :clients
610 # end
611 #
0432d151 » lifo 2008-07-16 Merge with docrails. Comment 612 # class Client < ActiveRecord::Base; end
db045dbb » dhh 2004-11-23 Initial 613 # end
614 # end
615 #
0432d151 » lifo 2008-07-16 Merge with docrails. Comment 616 # When <tt>Firm#clients</tt> is called, it will in turn call <tt>MyApplication::Business::Client.find_all_by_firm_id(firm.id)</tt>.
617 # If you want to associate with a class in another module scope, this can be done by specifying the complete class name.
618 # Example:
db045dbb » dhh 2004-11-23 Initial 619 #
620 # module MyApplication
621 # module Business
622 # class Firm < ActiveRecord::Base; end
623 # end
624 #
625 # module Billing
626 # class Account < ActiveRecord::Base
627 # belongs_to :firm, :class_name => "MyApplication::Business::Firm"
628 # end
629 # end
630 # end
631 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 632 # == Type safety with <tt>ActiveRecord::AssociationTypeMismatch</tt>
db045dbb » dhh 2004-11-23 Initial 633 #
634 # If you attempt to assign an object to an association that doesn't match the inferred or specified <tt>:class_name</tt>, you'll
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 635 # get an <tt>ActiveRecord::AssociationTypeMismatch</tt>.
db045dbb » dhh 2004-11-23 Initial 636 #
637 # == Options
638 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 639 # All of the association macros can be specialized through options. This makes cases more complex than the simple and guessable ones
db045dbb » dhh 2004-11-23 Initial 640 # possible.
641 module ClassMethods
6e754551 » lifo 2008-07-28 Merge docrails changes 642 # Specifies a one-to-many association. The following methods for retrieval and query of
643 # collections of associated objects will be added:
644 #
645 # [collection(force_reload = false)]
646 # Returns an array of all the associated objects.
db045dbb » dhh 2004-11-23 Initial 647 # An empty array is returned if none are found.
6e754551 » lifo 2008-07-28 Merge docrails changes 648 # [collection<<(object, ...)]
649 # Adds one or more objects to the collection by setting their foreign keys to the collection's primary key.
650 # [collection.delete(object, ...)]
651 # Removes one or more objects from the collection by setting their foreign keys to +NULL+.
a03e2b35 » lifo 2008-10-21 Merge with docrails. Also a... 652 # Objects will be in addition destroyed if they're associated with <tt>:dependent => :destroy</tt>,
653 # and deleted if they're associated with <tt>:dependent => :delete_all</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 654 # [collection=objects]
655 # Replaces the collections content by deleting and adding objects as appropriate.
656 # [collection_singular_ids]
657 # Returns an array of the associated objects' ids
658 # [collection_singular_ids=ids]
659 # Replace the collection with the objects identified by the primary keys in +ids+
660 # [collection.clear]
661 # Removes every object from the collection. This destroys the associated objects if they
662 # are associated with <tt>:dependent => :destroy</tt>, deletes them directly from the
663 # database if <tt>:dependent => :delete_all</tt>, otherwise sets their foreign keys to +NULL+.
664 # [collection.empty?]
665 # Returns +true+ if there are no associated objects.
666 # [collection.size]
667 # Returns the number of associated objects.
668 # [collection.find(...)]
669 # Finds an associated object according to the same rules as ActiveRecord::Base.find.
c3f53f41 » lifo 2008-12-19 Merge docrails 670 # [collection.exists?(...)]
6e754551 » lifo 2008-07-28 Merge docrails changes 671 # Checks whether an associated object with the given conditions exists.
672 # Uses the same rules as ActiveRecord::Base.exists?.
673 # [collection.build(attributes = {}, ...)]
674 # Returns one or more new objects of the collection type that have been instantiated
675 # with +attributes+ and linked to this object through a foreign key, but have not yet
676 # been saved. <b>Note:</b> This only works if an associated object already exists, not if
677 # it's +nil+!
678 # [collection.create(attributes = {})]
679 # Returns a new object of the collection type that has been instantiated
680 # with +attributes+, linked to this object through a foreign key, and that has already
681 # been saved (if it passed the validation). <b>Note:</b> This only works if an associated
682 # object already exists, not if it's +nil+!
683 #
684 # (*Note*: +collection+ is replaced with the symbol passed as the first argument, so
685 # <tt>has_many :clients</tt> would add among others <tt>clients.empty?</tt>.)
686 #
687 # === Example
db045dbb » dhh 2004-11-23 Initial 688 #
6ef35461 » lifo 2008-09-03 Merge docrails 689 # Example: A Firm class declares <tt>has_many :clients</tt>, which will add:
690 # * <tt>Firm#clients</tt> (similar to <tt>Clients.find :all, :conditions => ["firm_id = ?", id]</tt>)
db045dbb » dhh 2004-11-23 Initial 691 # * <tt>Firm#clients<<</tt>
692 # * <tt>Firm#clients.delete</tt>
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 693 # * <tt>Firm#clients=</tt>
cb0837a2 » dhh 2006-10-08 Doc fixes (closes #6325) 694 # * <tt>Firm#client_ids</tt>
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 695 # * <tt>Firm#client_ids=</tt>
db045dbb » dhh 2004-11-23 Initial 696 # * <tt>Firm#clients.clear</tt>
697 # * <tt>Firm#clients.empty?</tt> (similar to <tt>firm.clients.size == 0</tt>)
698 # * <tt>Firm#clients.size</tt> (similar to <tt>Client.count "firm_id = #{id}"</tt>)
c1611a70 » dhh 2005-04-18 Updated documentation here ... 699 # * <tt>Firm#clients.find</tt> (similar to <tt>Client.find(id, :conditions => "firm_id = #{id}")</tt>)
c3f53f41 » lifo 2008-12-19 Merge docrails 700 # * <tt>Firm#clients.exists?(:name => 'ACME')</tt> (similar to <tt>Client.exists?(:name => 'ACME', :firm_id => firm.id)</tt>)
db045dbb » dhh 2004-11-23 Initial 701 # * <tt>Firm#clients.build</tt> (similar to <tt>Client.new("firm_id" => id)</tt>)
1d4d7217 » dhh 2005-06-21 Fixed docs #856 702 # * <tt>Firm#clients.create</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save; c</tt>)
db045dbb » dhh 2004-11-23 Initial 703 # The declaration can also include an options hash to specialize the behavior of the association.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 704 #
6e754551 » lifo 2008-07-28 Merge docrails changes 705 # === Supported options
706 # [:class_name]
707 # Specify the class name of the association. Use it only if that name can't be inferred
dc4eec11 » lifo 2008-05-09 Merge docrails: 708 # from the association name. So <tt>has_many :products</tt> will by default be linked to the Product class, but
709 # if the real class name is SpecialProduct, you'll have to specify it with this option.
6e754551 » lifo 2008-07-28 Merge docrails changes 710 # [:conditions]
711 # Specify the conditions that the associated objects must meet in order to be included as a +WHERE+
c23c9bd1 » technoweenie 2008-03-21 Allow association scoping f... 712 # SQL fragment, such as <tt>price > 5 AND name LIKE 'B%'</tt>. Record creations from the association are scoped if a hash
713 # is used. <tt>has_many :posts, :conditions => {:published => true}</tt> will create published posts with <tt>@blog.posts.create</tt>
714 # or <tt>@blog.posts.build</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 715 # [:order]
716 # Specify the order in which the associated objects are returned as an <tt>ORDER BY</tt> SQL fragment,
dc4eec11 » lifo 2008-05-09 Merge docrails: 717 # such as <tt>last_name, first_name DESC</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 718 # [:foreign_key]
719 # Specify the foreign key used for the association. By default this is guessed to be the name
dc4eec11 » lifo 2008-05-09 Merge docrails: 720 # of this class in lower-case and "_id" suffixed. So a Person class that makes a +has_many+ association will use "person_id"
721 # as the default <tt>:foreign_key</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 722 # [:primary_key]
723 # Specify the method that returns the primary key used for the association. By default this is +id+.
724 # [:dependent]
725 # If set to <tt>:destroy</tt> all the associated objects are destroyed
dc4eec11 » lifo 2008-05-09 Merge docrails: 726 # alongside this object by calling their +destroy+ method. If set to <tt>:delete_all</tt> all associated
727 # objects are deleted *without* calling their +destroy+ method. If set to <tt>:nullify</tt> all associated
728 # objects' foreign keys are set to +NULL+ *without* calling their +save+ callbacks. *Warning:* This option is ignored when also using
729 # the <tt>:through</tt> option.
6e754551 » lifo 2008-07-28 Merge docrails changes 730 # [:finder_sql]
731 # Specify a complete SQL statement to fetch the association. This is a good way to go for complex
a8eea0b0 » dhh 2005-10-26 Fix docs (closes #2491) 732 # associations that depend on multiple tables. Note: When this option is used, +find_in_collection+ is _not_ added.
6e754551 » lifo 2008-07-28 Merge docrails changes 733 # [:counter_sql]
734 # Specify a complete SQL statement to fetch the size of the association. If <tt>:finder_sql</tt> is
7143d801 » Marcel Molina 2007-11-07 Smattering of grammatical f... 735 # specified but not <tt>:counter_sql</tt>, <tt>:counter_sql</tt> will be generated by replacing <tt>SELECT ... FROM</tt> with <tt>SELECT COUNT(*) FROM</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 736 # [:extend]
737 # Specify a named module for extending the proxy. See "Association extensions".
738 # [:include]
739 # Specify second-order associations that should be eager loaded when the collection is loaded.
740 # [:group]
741 # An attribute name by which the result should be grouped. Uses the <tt>GROUP BY</tt> SQL-clause.
97403ad5 » miloops 2008-11-21 Add :having option to find,... 742 # [:having]
743 # Combined with +:group+ this can be used to filter the records that a <tt>GROUP BY</tt> returns. Uses the <tt>HAVING</tt> SQL-clause.
6e754551 » lifo 2008-07-28 Merge docrails changes 744 # [:limit]
745 # An integer determining the limit on the number of rows that should be returned.
746 # [:offset]
747 # An integer determining the offset from where the rows should be fetched. So at 5, it would skip the first 4 rows.
748 # [:select]
749 # By default, this is <tt>*</tt> as in <tt>SELECT * FROM</tt>, but can be changed if you, for example, want to do a join
3351d299 » indirect 2008-05-31 Add has_many :primary_key o... 750 # but not include the joined columns. Do not forget to include the primary and foreign keys, otherwise it will raise an error.
6e754551 » lifo 2008-07-28 Merge docrails changes 751 # [:as]
752 # Specifies a polymorphic interface (See <tt>belongs_to</tt>).
753 # [:through]
754 # Specifies a Join Model through which to perform the query. Options for <tt>:class_name</tt> and <tt>:foreign_key</tt>
9f51eb24 » jeremy 2007-05-22 Fix :through docs wrecked u... 755 # are ignored, as the association uses the source reflection. You can only use a <tt>:through</tt> query through a <tt>belongs_to</tt>
756 # or <tt>has_many</tt> association on the join model.
6e754551 » lifo 2008-07-28 Merge docrails changes 757 # [:source]
758 # Specifies the source association name used by <tt>has_many :through</tt> queries. Only use it if the name cannot be
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 759 # inferred from the association. <tt>has_many :subscribers, :through => :subscriptions</tt> will look for either <tt>:subscribers</tt> or
dc4eec11 » lifo 2008-05-09 Merge docrails: 760 # <tt>:subscriber</tt> on Subscription, unless a <tt>:source</tt> is given.
6e754551 » lifo 2008-07-28 Merge docrails changes 761 # [:source_type]
762 # Specifies type of the source association used by <tt>has_many :through</tt> queries where the source
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 763 # association is a polymorphic +belongs_to+.
6e754551 » lifo 2008-07-28 Merge docrails changes 764 # [:uniq]
765 # If true, duplicates will be omitted from the collection. Useful in conjunction with <tt>:through</tt>.
766 # [:readonly]
767 # If true, all the associated objects are readonly through the association.
768 # [:validate]
769 # If false, don't validate the associated objects when saving the parent object. true by default.
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 770 # [:autosave]
771 # If true, always save any loaded members and destroy members marked for destruction, when saving the parent object. Off by default.
772 #
db045dbb » dhh 2004-11-23 Initial 773 # Option examples:
774 # has_many :comments, :order => "posted_on"
49c801b7 » dhh 2005-11-06 Added :include as an option... 775 # has_many :comments, :include => :author
db045dbb » dhh 2004-11-23 Initial 776 # has_many :people, :class_name => "Person", :conditions => "deleted = 0", :order => "name"
57565b35 » NZKoz 2006-03-09 format fix for locking [Mic... 777 # has_many :tracks, :order => "position", :dependent => :destroy
778 # has_many :comments, :dependent => :nullify
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 779 # has_many :tags, :as => :taggable
dfa78663 » jeremy 2008-02-12 Introduce the :readonly opt... 780 # has_many :reports, :readonly => true
38bae0a9 » technoweenie 2006-03-24 Change has_many :through to... 781 # has_many :subscribers, :through => :subscriptions, :source => :user
db045dbb » dhh 2004-11-23 Initial 782 # has_many :subscribers, :class_name => "Person", :finder_sql =>
783 # 'SELECT DISTINCT people.* ' +
784 # 'FROM people p, post_subscriptions ps ' +
785 # 'WHERE ps.post_id = #{id} AND ps.person_id = p.id ' +
786 # 'ORDER BY p.first_name'
c8dd66fd » dhh 2005-11-06 Made association extensions... 787 def has_many(association_id, options = {}, &extension)
6abda696 » dhh 2005-12-02 Added preliminary support f... 788 reflection = create_has_many_reflection(association_id, options, &extension)
789 configure_dependency_for_has_many(reflection)
f6b12c11 » lifo 2008-04-05 Refactor HasManyThroughAsso... 790 add_association_callbacks(reflection.name, reflection.options)
791
6abda696 » dhh 2005-12-02 Added preliminary support f... 792 if options[:through]
f6b12c11 » lifo 2008-04-05 Refactor HasManyThroughAsso... 793 collection_accessor_methods(reflection, HasManyThroughAssociation)
6abda696 » dhh 2005-12-02 Added preliminary support f... 794 else
795 collection_accessor_methods(reflection, HasManyAssociation)
db045dbb » dhh 2004-11-23 Initial 796 end
797 end
798
6e754551 » lifo 2008-07-28 Merge docrails changes 799 # Specifies a one-to-one association with another class. This method should only be used
800 # if the other class contains the foreign key. If the current class contains the foreign key,
801 # then you should use +belongs_to+ instead. See also ActiveRecord::Associations::ClassMethods's overview
802 # on when to use has_one and when to use belongs_to.
803 #
804 # The following methods for retrieval and query of a single associated object will be added:
805 #
806 # [association(force_reload = false)]
807 # Returns the associated object. +nil+ is returned if none is found.
808 # [association=(associate)]
809 # Assigns the associate object, extracts the primary key, sets it as the foreign key,
db045dbb » dhh 2004-11-23 Initial 810 # and saves the associate object.
6e754551 » lifo 2008-07-28 Merge docrails changes 811 # [build_association(attributes = {})]
812 # Returns a new object of the associated type that has been instantiated
813 # with +attributes+ and linked to this object through a foreign key, but has not
814 # yet been saved. <b>Note:</b> This ONLY works if an association already exists.
815 # It will NOT work if the association is +nil+.
816 # [create_association(attributes = {})]
817 # Returns a new object of the associated type that has been instantiated
818 # with +attributes+, linked to this object through a foreign key, and that
819 # has already been saved (if it passed the validation).
820 #
821 # (+association+ is replaced with the symbol passed as the first argument, so
822 # <tt>has_one :manager</tt> would add among others <tt>manager.nil?</tt>.)
db045dbb » dhh 2004-11-23 Initial 823 #
6e754551 » lifo 2008-07-28 Merge docrails changes 824 # === Example
825 #
826 # An Account class declares <tt>has_one :beneficiary</tt>, which will add:
3dfa56cc » dhh 2005-06-26 Updated all references to t... 827 # * <tt>Account#beneficiary</tt> (similar to <tt>Beneficiary.find(:first, :conditions => "account_id = #{id}")</tt>)
db045dbb » dhh 2004-11-23 Initial 828 # * <tt>Account#beneficiary=(beneficiary)</tt> (similar to <tt>beneficiary.account_id = account.id; beneficiary.save</tt>)
3b9e90a4 » dhh 2005-04-11 Moved build_association and... 829 # * <tt>Account#build_beneficiary</tt> (similar to <tt>Beneficiary.new("account_id" => id)</tt>)
830 # * <tt>Account#create_beneficiary</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save; b</tt>)
831 #
6e754551 » lifo 2008-07-28 Merge docrails changes 832 # === Options
833 #
db045dbb » dhh 2004-11-23 Initial 834 # The declaration can also include an options hash to specialize the behavior of the association.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 835 #
db045dbb » dhh 2004-11-23 Initial 836 # Options are:
6e754551 » lifo 2008-07-28 Merge docrails changes 837 # [:class_name]
838 # Specify the class name of the association. Use it only if that name can't be inferred
dc4eec11 » lifo 2008-05-09 Merge docrails: 839 # from the association name. So <tt>has_one :manager</tt> will by default be linked to the Manager class, but
840 # if the real class name is Person, you'll have to specify it with this option.
6e754551 » lifo 2008-07-28 Merge docrails changes 841 # [:conditions]
842 # Specify the conditions that the associated object must meet in order to be included as a +WHERE+
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 843 # SQL fragment, such as <tt>rank = 5</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 844 # [:order]
845 # Specify the order in which the associated objects are returned as an <tt>ORDER BY</tt> SQL fragment,
dc4eec11 » lifo 2008-05-09 Merge docrails: 846 # such as <tt>last_name, first_name DESC</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 847 # [:dependent]
848 # If set to <tt>:destroy</tt>, the associated object is destroyed when this object is. If set to
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 849 # <tt>:delete</tt>, the associated object is deleted *without* calling its destroy method. If set to <tt>:nullify</tt>, the associated
850 # object's foreign key is set to +NULL+. Also, association is assigned.
6e754551 » lifo 2008-07-28 Merge docrails changes 851 # [:foreign_key]
852 # Specify the foreign key used for the association. By default this is guessed to be the name
dc4eec11 » lifo 2008-05-09 Merge docrails: 853 # of this class in lower-case and "_id" suffixed. So a Person class that makes a +has_one+ association will use "person_id"
854 # as the default <tt>:foreign_key</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 855 # [:primary_key]
856 # Specify the method that returns the primary key used for the association. By default this is +id+.
857 # [:include]
858 # Specify second-order associations that should be eager loaded when this object is loaded.
859 # [:as]
860 # Specifies a polymorphic interface (See <tt>belongs_to</tt>).
861 # [:select]
862 # By default, this is <tt>*</tt> as in <tt>SELECT * FROM</tt>, but can be changed if, for example, you want to do a join
8d0b4fa3 » josevalim 2008-05-23 Added :select option to has... 863 # but not include the joined columns. Do not forget to include the primary and foreign keys, otherwise it will raise an error.
6e754551 » lifo 2008-07-28 Merge docrails changes 864 # [:through]
865 # Specifies a Join Model through which to perform the query. Options for <tt>:class_name</tt> and <tt>:foreign_key</tt>
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 866 # are ignored, as the association uses the source reflection. You can only use a <tt>:through</tt> query through a
867 # <tt>has_one</tt> or <tt>belongs_to</tt> association on the join model.
6e754551 » lifo 2008-07-28 Merge docrails changes 868 # [:source]
869 # Specifies the source association name used by <tt>has_one :through</tt> queries. Only use it if the name cannot be
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 870 # inferred from the association. <tt>has_one :favorite, :through => :favorites</tt> will look for a
5cda000b » dhh 2009-02-27 Fixed that autosave should ... Comment 871 # <tt>:favorite</tt> on Favorite, unless a <tt>:source</tt> is given.
6e754551 » lifo 2008-07-28 Merge docrails changes 872 # [:source_type]
873 # Specifies type of the source association used by <tt>has_one :through</tt> queries where the source
5cda000b » dhh 2009-02-27 Fixed that autosave should ... Comment 874 # association is a polymorphic +belongs_to+.
6e754551 » lifo 2008-07-28 Merge docrails changes 875 # [:readonly]
876 # If true, the associated object is readonly through the association.
877 # [:validate]
878 # If false, don't validate the associated object when saving the parent object. +false+ by default.
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 879 # [:autosave]
880 # If true, always save the associated object or destroy it if marked for destruction, when saving the parent object. Off by default.
dfa78663 » jeremy 2008-02-12 Introduce the :readonly opt... 881 #
db045dbb » dhh 2004-11-23 Initial 882 # Option examples:
57565b35 » NZKoz 2006-03-09 format fix for locking [Mic... 883 # has_one :credit_card, :dependent => :destroy # destroys the associated credit card
7143d801 » Marcel Molina 2007-11-07 Smattering of grammatical f... 884 # has_one :credit_card, :dependent => :nullify # updates the associated records foreign key value to NULL rather than destroying it
db045dbb » dhh 2004-11-23 Initial 885 # has_one :last_comment, :class_name => "Comment", :order => "posted_on"
886 # has_one :project_manager, :class_name => "Person", :conditions => "role = 'project_manager'"
21399219 » technoweenie 2006-05-22 Add docs for the :as option... 887 # has_one :attachment, :as => :attachable
dfa78663 » jeremy 2008-02-12 Introduce the :readonly opt... 888 # has_one :boss, :readonly => :true
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 889 # has_one :club, :through => :membership
890 # has_one :primary_address, :through => :addressables, :conditions => ["addressable.primary = ?", true], :source => :addressable
db045dbb » dhh 2004-11-23 Initial 891 def has_one(association_id, options = {})
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 892 if options[:through]
893 reflection = create_has_one_through_reflection(association_id, options)
894 association_accessor_methods(reflection, ActiveRecord::Associations::HasOneThroughAssociation)
895 else
896 reflection = create_has_one_reflection(association_id, options)
897 association_accessor_methods(reflection, HasOneAssociation)
898 association_constructor_method(:build, reflection, HasOneAssociation)
899 association_constructor_method(:create, reflection, HasOneAssociation)
900 configure_dependency_for_has_one(reflection)
901 end
db045dbb » dhh 2004-11-23 Initial 902 end
903
6e754551 » lifo 2008-07-28 Merge docrails changes 904 # Specifies a one-to-one association with another class. This method should only be used
905 # if this class contains the foreign key. If the other class contains the foreign key,
906 # then you should use +has_one+ instead. See also ActiveRecord::Associations::ClassMethods's overview
907 # on when to use +has_one+ and when to use +belongs_to+.
908 #
909 # Methods will be added for retrieval and query for a single associated object, for which
910 # this object holds an id:
911 #
912 # [association(force_reload = false)]
913 # Returns the associated object. +nil+ is returned if none is found.
914 # [association=(associate)]
915 # Assigns the associate object, extracts the primary key, and sets it as the foreign key.
916 # [build_association(attributes = {})]
917 # Returns a new object of the associated type that has been instantiated
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 918 # with +attributes+ and linked to this object through a foreign key, but has not yet been saved.
6e754551 » lifo 2008-07-28 Merge docrails changes 919 # [create_association(attributes = {})]
920 # Returns a new object of the associated type that has been instantiated
921 # with +attributes+, linked to this object through a foreign key, and that
922 # has already been saved (if it passed the validation).
923 #
924 # (+association+ is replaced with the symbol passed as the first argument, so
925 # <tt>belongs_to :author</tt> would add among others <tt>author.nil?</tt>.)
db045dbb » dhh 2004-11-23 Initial 926 #
6e754551 » lifo 2008-07-28 Merge docrails changes 927 # === Example
928 #
929 # A Post class declares <tt>belongs_to :author</tt>, which will add:
db045dbb » dhh 2004-11-23 Initial 930 # * <tt>Post#author</tt> (similar to <tt>Author.find(author_id)</tt>)
931 # * <tt>Post#author=(author)</tt> (similar to <tt>post.author_id = author.id</tt>)
932 # * <tt>Post#author?</tt> (similar to <tt>post.author == some_author</tt>)
1d4d7217 » dhh 2005-06-21 Fixed docs #856 933 # * <tt>Post#build_author</tt> (similar to <tt>post.author = Author.new</tt>)
934 # * <tt>Post#create_author</tt> (similar to <tt>post.author = Author.new; post.author.save; post.author</tt>)
db045dbb » dhh 2004-11-23 Initial 935 # The declaration can also include an options hash to specialize the behavior of the association.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 936 #
6e754551 » lifo 2008-07-28 Merge docrails changes 937 # === Options
938 #
939 # [:class_name]
940 # Specify the class name of the association. Use it only if that name can't be inferred
dc4eec11 » lifo 2008-05-09 Merge docrails: 941 # from the association name. So <tt>has_one :author</tt> will by default be linked to the Author class, but
942 # if the real class name is Person, you'll have to specify it with this option.
6e754551 » lifo 2008-07-28 Merge docrails changes 943 # [:conditions]
944 # Specify the conditions that the associated object must meet in order to be included as a +WHERE+
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 945 # SQL fragment, such as <tt>authorized = 1</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 946 # [:select]
947 # By default, this is <tt>*</tt> as in <tt>SELECT * FROM</tt>, but can be changed if, for example, you want to do a join
8d0b4fa3 » josevalim 2008-05-23 Added :select option to has... 948 # but not include the joined columns. Do not forget to include the primary and foreign keys, otherwise it will raise an error.
6e754551 » lifo 2008-07-28 Merge docrails changes 949 # [:foreign_key]
950 # Specify the foreign key used for the association. By default this is guessed to be the name
dc4eec11 » lifo 2008-05-09 Merge docrails: 951 # of the association with an "_id" suffix. So a class that defines a <tt>belongs_to :person</tt> association will use
952 # "person_id" as the default <tt>:foreign_key</tt>. Similarly, <tt>belongs_to :favorite_person, :class_name => "Person"</tt>
953 # will use a foreign key of "favorite_person_id".
6e754551 » lifo 2008-07-28 Merge docrails changes 954 # [:dependent]
955 # If set to <tt>:destroy</tt>, the associated object is destroyed when this object is. If set to
16b129a6 » jeremy 2008-01-18 belongs_to supports :depend... 956 # <tt>:delete</tt>, the associated object is deleted *without* calling its destroy method. This option should not be specified when
957 # <tt>belongs_to</tt> is used in conjunction with a <tt>has_many</tt> relationship on another class because of the potential to leave
958 # orphaned records behind.
6e754551 » lifo 2008-07-28 Merge docrails changes 959 # [:counter_cache]
960 # Caches the number of belonging objects on the associate class through the use of +increment_counter+
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 961 # and +decrement_counter+. The counter cache is incremented when an object of this class is created and decremented when it's
dc4eec11 » lifo 2008-05-09 Merge docrails: 962 # destroyed. This requires that a column named <tt>#{table_name}_count</tt> (such as +comments_count+ for a belonging Comment class)
963 # is used on the associate class (such as a Post class). You can also specify a custom counter cache column by providing
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 964 # a column name instead of a +true+/+false+ value to this option (e.g., <tt>:counter_cache => :my_custom_counter</tt>.)
dc4eec11 » lifo 2008-05-09 Merge docrails: 965 # Note: Specifying a counter cache will add it to that model's list of readonly attributes using +attr_readonly+.
6e754551 » lifo 2008-07-28 Merge docrails changes 966 # [:include]
967 # Specify second-order associations that should be eager loaded when this object is loaded.
968 # [:polymorphic]
969 # Specify this association is a polymorphic association by passing +true+.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 970 # Note: If you've enabled the counter cache, then you may want to add the counter cache attribute
dc4eec11 » lifo 2008-05-09 Merge docrails: 971 # to the +attr_readonly+ list in the associated classes (e.g. <tt>class Post; attr_readonly :comments_count; end</tt>).
6e754551 » lifo 2008-07-28 Merge docrails changes 972 # [:readonly]
973 # If true, the associated object is readonly through the association.
974 # [:validate]
975 # If false, don't validate the associated objects when saving the parent object. +false+ by default.
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 976 # [:autosave]
977 # If true, always save the associated object or destroy it if marked for destruction, when saving the parent object. Off by default.
db045dbb » dhh 2004-11-23 Initial 978 #
979 # Option examples:
980 # belongs_to :firm, :foreign_key => "client_of"
981 # belongs_to :author, :class_name => "Person", :foreign_key => "author_id"
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 982 # belongs_to :valid_coupon, :class_name => "Coupon", :foreign_key => "coupon_id",
db045dbb » dhh 2004-11-23 Initial 983 # :conditions => 'discounts > #{payments_count}'
2597bd69 » technoweenie 2006-03-27 documentation for polymorph... 984 # belongs_to :attachable, :polymorphic => true
dfa78663 » jeremy 2008-02-12 Introduce the :readonly opt... 985 # belongs_to :project, :readonly => true
54213dad » dhh 2008-03-19 Docfixes (closes #11356, #1... 986 # belongs_to :post, :counter_cache => true
823554ea » dhh 2005-01-15 Added support for associati... 987 def belongs_to(association_id, options = {})
6abda696 » dhh 2005-12-02 Added preliminary support f... 988 reflection = create_belongs_to_reflection(association_id, options)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 989
6abda696 » dhh 2005-12-02 Added preliminary support f... 990 if reflection.options[:polymorphic]
991 association_accessor_methods(reflection, BelongsToPolymorphicAssociation)
57b7532b » dhh 2005-12-01 Work-in progress for provid... 992 else
6abda696 » dhh 2005-12-02 Added preliminary support f... 993 association_accessor_methods(reflection, BelongsToAssociation)
994 association_constructor_method(:build, reflection, BelongsToAssociation)
995 association_constructor_method(:create, reflection, BelongsToAssociation)
57b7532b » dhh 2005-12-01 Work-in progress for provid... 996 end
964b67dd » jamis 2006-03-04 Make counter_cache work wit... 997
2a305949 » technoweenie 2007-03-27 documentation project patch... 998 # Create the callbacks to update counter cache
964b67dd » jamis 2006-03-04 Make counter_cache work wit... 999 if options[:counter_cache]
87898bad » jamis 2006-03-09 Allow counter_cache to acce... 1000 cache_column = options[:counter_cache] == true ?
de96a866 » adevadeh 2008-09-12 applied patch to fix the as... 1001 "#{self.to_s.demodulize.underscore.pluralize}_count" :
87898bad » jamis 2006-03-09 Allow counter_cache to acce... 1002 options[:counter_cache]
1003
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1004 method_name = "belongs_to_counter_cache_after_create_for_#{reflection.name}".to_sym
1005 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1006 association = send(reflection.name)
1007 association.class.increment_counter(cache_column, send(reflection.primary_key_name)) unless association.nil?
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1008 end
1009 after_create method_name
964b67dd » jamis 2006-03-04 Make counter_cache work wit... 1010
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1011 method_name = "belongs_to_counter_cache_before_destroy_for_#{reflection.name}".to_sym
1012 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1013 association = send(reflection.name)
1014 association.class.decrement_counter(cache_column, send(reflection.primary_key_name)) unless association.nil?
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1015 end
1016 before_destroy method_name
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1017
66d05f5e » technoweenie 2007-09-30 Add attr_readonly to specif... 1018 module_eval(
24c2457a » technoweenie 2007-10-05 Don't call attr_readonly on... 1019 "#{reflection.class_name}.send(:attr_readonly,\"#{cache_column}\".intern) if defined?(#{reflection.class_name}) && #{reflection.class_name}.respond_to?(:attr_readonly)"
66d05f5e » technoweenie 2007-09-30 Add attr_readonly to specif... 1020 )
964b67dd » jamis 2006-03-04 Make counter_cache work wit... 1021 end
16b129a6 » jeremy 2008-01-18 belongs_to supports :depend... 1022
1023 configure_dependency_for_belongs_to(reflection)
823554ea » dhh 2005-01-15 Added support for associati... 1024 end
1025
6e754551 » lifo 2008-07-28 Merge docrails changes 1026 # Specifies a many-to-many relationship with another class. This associates two classes via an
1027 # intermediate join table. Unless the join table is explicitly specified as an option, it is
1028 # guessed using the lexical order of the class names. So a join between Developer and Project
dc4eec11 » lifo 2008-05-09 Merge docrails: 1029 # will give the default join table name of "developers_projects" because "D" outranks "P". Note that this precedence
1030 # is calculated using the <tt><</tt> operator for String. This means that if the strings are of different lengths,
56c55354 » technoweenie 2007-01-15 [DOC] clear up some ambigui... 1031 # and the strings are equal when compared up to the shortest length, then the longer string is considered of higher
dc4eec11 » lifo 2008-05-09 Merge docrails: 1032 # lexical precedence than the shorter one. For example, one would expect the tables "paper_boxes" and "papers"
1033 # to generate a join table name of "papers_paper_boxes" because of the length of the name "paper_boxes",
1034 # but it in fact generates a join table name of "paper_boxes_papers". Be aware of this caveat, and use the
1035 # custom <tt>:join_table</tt> option if you need to.
db045dbb » dhh 2004-11-23 Initial 1036 #
96d61055 » lifo 2009-02-05 Merge docrails along with t... 1037 # The join table should not have a primary key or a model associated with it. You must manually generate the
1038 # join table with a migration such as this:
1039 #
1040 # class CreateDevelopersProjectsJoinTable < ActiveRecord::Migration
1041 # def self.up
1042 # create_table :developers_projects, :id => false do |t|
1043 # t.integer :developer_id
1044 # t.integer :project_id
1045 # end
1046 # end
1047 #
1048 # def self.down
1049 # drop_table :developers_projects
1050 # end
1051 # end
1052 #
53aa8da1 » dhh 2006-04-01 Fixed that records returned... 1053 # Deprecated: Any additional fields added to the join table will be placed as attributes when pulling records out through
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1054 # +has_and_belongs_to_many+ associations. Records returned from join tables with additional attributes will be marked as
98dc5827 » lifo 2008-05-25 Merge docrails. Comment 1055 # readonly (because we can't save changes to the additional attributes). It's strongly recommended that you upgrade any
53aa8da1 » dhh 2006-04-01 Fixed that records returned... 1056 # associations with attributes to a real join model (see introduction).
db045dbb » dhh 2004-11-23 Initial 1057 #
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1058 # Adds the following methods for retrieval and query:
6e754551 » lifo 2008-07-28 Merge docrails changes 1059 #
1060 # [collection(force_reload = false)]
1061 # Returns an array of all the associated objects.
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1062 # An empty array is returned if none are found.
6e754551 » lifo 2008-07-28 Merge docrails changes 1063 # [collection<<(object, ...)]
1064 # Adds one or more objects to the collection by creating associations in the join table
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1065 # (<tt>collection.push</tt> and <tt>collection.concat</tt> are aliases to this method).
6e754551 » lifo 2008-07-28 Merge docrails changes 1066 # [collection.delete(object, ...)]
1067 # Removes one or more objects from the collection by removing their associations from the join table.
db045dbb » dhh 2004-11-23 Initial 1068 # This does not destroy the objects.
6e754551 » lifo 2008-07-28 Merge docrails changes 1069 # [collection=objects]
1070 # Replaces the collection's content by deleting and adding objects as appropriate.
1071 # [collection_singular_ids]
1072 # Returns an array of the associated objects' ids.
1073 # [collection_singular_ids=ids]
1074 # Replace the collection by the objects identified by the primary keys in +ids+.
1075 # [collection.clear]
1076 # Removes every object from the collection. This does not destroy the objects.
1077 # [collection.empty?]
1078 # Returns +true+ if there are no associated objects.
1079 # [collection.size]
1080 # Returns the number of associated objects.
1081 # [collection.find(id)]
1082 # Finds an associated object responding to the +id+ and that
823554ea » dhh 2005-01-15 Added support for associati... 1083 # meets the condition that it has to be associated with this object.
6e754551 » lifo 2008-07-28 Merge docrails changes 1084 # Uses the same rules as ActiveRecord::Base.find.
c3f53f41 » lifo 2008-12-19 Merge docrails 1085 # [collection.exists?(...)]
6e754551 » lifo 2008-07-28 Merge docrails changes 1086 # Checks whether an associated object with the given conditions exists.
1087 # Uses the same rules as ActiveRecord::Base.exists?.
1088 # [collection.build(attributes = {})]
1089 # Returns a new object of the collection type that has been instantiated
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1090 # with +attributes+ and linked to this object through the join table, but has not yet been saved.
6e754551 » lifo 2008-07-28 Merge docrails changes 1091 # [collection.create(attributes = {})]
1092 # Returns a new object of the collection type that has been instantiated
18a3333a » NZKoz 2007-08-28 Formatting, grammar and spe... 1093 # with +attributes+, linked to this object through the join table, and that has already been saved (if it passed the validation).
db045dbb » dhh 2004-11-23 Initial 1094 #
6e754551 » lifo 2008-07-28 Merge docrails changes 1095 # (+collection+ is replaced with the symbol passed as the first argument, so
1096 # <tt>has_and_belongs_to_many :categories</tt> would add among others <tt>categories.empty?</tt>.)
1097 #
1098 # === Example
1099 #
1100 # A Developer class declares <tt>has_and_belongs_to_many :projects</tt>, which will add:
db045dbb » dhh 2004-11-23 Initial 1101 # * <tt>Developer#projects</tt>
1102 # * <tt>Developer#projects<<</tt>
1103 # * <tt>Developer#projects.delete</tt>
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 1104 # * <tt>Developer#projects=</tt>
cb0837a2 » dhh 2006-10-08 Doc fixes (closes #6325) 1105 # * <tt>Developer#project_ids</tt>
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 1106 # * <tt>Developer#project_ids=</tt>
db045dbb » dhh 2004-11-23 Initial 1107 # * <tt>Developer#projects.clear</tt>
1108 # * <tt>Developer#projects.empty?</tt>
1109 # * <tt>Developer#projects.size</tt>
1110 # * <tt>Developer#projects.find(id)</tt>
c3f53f41 » lifo 2008-12-19 Merge docrails 1111 # * <tt>Developer#clients.exists?(...)</tt>
06075a9e » technoweenie 2006-05-28 Fix the has_and_belongs_to_... 1112 # * <tt>Developer#projects.build</tt> (similar to <tt>Project.new("project_id" => id)</tt>)
1113 # * <tt>Developer#projects.create</tt> (similar to <tt>c = Project.new("project_id" => id); c.save; c</tt>)
db045dbb » dhh 2004-11-23 Initial 1114 # The declaration may include an options hash to specialize the behavior of the association.
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1115 #
6e754551 » lifo 2008-07-28 Merge docrails changes 1116 # === Options
1117 #
1118 # [:class_name]
1119 # Specify the class name of the association. Use it only if that name can't be inferred
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1120 # from the association name. So <tt>has_and_belongs_to_many :projects</tt> will by default be linked to the
dc4eec11 » lifo 2008-05-09 Merge docrails: 1121 # Project class, but if the real class name is SuperProject, you'll have to specify it with this option.
6e754551 » lifo 2008-07-28 Merge docrails changes 1122 # [:join_table]
1123 # Specify the name of the join table if the default based on lexical order isn't what you want.
1124 # <b>WARNING:</b> If you're overwriting the table name of either class, the +table_name+ method
1125 # MUST be declared underneath any +has_and_belongs_to_many+ declaration in order to work.
1126 # [:foreign_key]
1127 # Specify the foreign key used for the association. By default this is guessed to be the name
dc4eec11 » lifo 2008-05-09 Merge docrails: 1128 # of this class in lower-case and "_id" suffixed. So a Person class that makes a +has_and_belongs_to_many+ association
886124e6 » lifo 2009-02-01 Merge docrails 1129 # to Project will use "person_id" as the default <tt>:foreign_key</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 1130 # [:association_foreign_key]
886124e6 » lifo 2009-02-01 Merge docrails 1131 # Specify the foreign key used for the association on the receiving side of the association.
1132 # By default this is guessed to be the name of the associated class in lower-case and "_id" suffixed.
1133 # So if a Person class makes a +has_and_belongs_to_many+ association to Project,
1134 # the association will use "project_id" as the default <tt>:association_foreign_key</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 1135 # [:conditions]
1136 # Specify the conditions that the associated object must meet in order to be included as a +WHERE+
c23c9bd1 » technoweenie 2008-03-21 Allow association scoping f... 1137 # SQL fragment, such as <tt>authorized = 1</tt>. Record creations from the association are scoped if a hash is used.
1138 # <tt>has_many :posts, :conditions => {:published => true}</tt> will create published posts with <tt>@blog.posts.create</tt>
1139 # or <tt>@blog.posts.build</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 1140 # [:order]
1141 # Specify the order in which the associated objects are returned as an <tt>ORDER BY</tt> SQL fragment,
7143d801 » Marcel Molina 2007-11-07 Smattering of grammatical f... 1142 # such as <tt>last_name, first_name DESC</tt>
6e754551 » lifo 2008-07-28 Merge docrails changes 1143 # [:uniq]
1144 # If true, duplicate associated objects will be ignored by accessors and query methods.
1145 # [:finder_sql]
1146 # Overwrite the default generated SQL statement used to fetch the association with a manual statement
44af2efa » ernie 2008-08-28 Refactored AssociationColle... 1147 # [:counter_sql]
1148 # Specify a complete SQL statement to fetch the size of the association. If <tt>:finder_sql</tt> is
1149 # specified but not <tt>:counter_sql</tt>, <tt>:counter_sql</tt> will be generated by replacing <tt>SELECT ... FROM</tt> with <tt>SELECT COUNT(*) FROM</tt>.
6e754551 » lifo 2008-07-28 Merge docrails changes 1150 # [:delete_sql]
1151 # Overwrite the default generated SQL statement used to remove links between the associated
dc4eec11 » lifo 2008-05-09 Merge docrails: 1152 # classes with a manual statement.
6e754551 » lifo 2008-07-28 Merge docrails changes 1153 # [:insert_sql]
1154 # Overwrite the default generated SQL statement used to add links between the associated classes
dc4eec11 » lifo 2008-05-09 Merge docrails: 1155 # with a manual statement.
6e754551 » lifo 2008-07-28 Merge docrails changes 1156 # [:extend]
1157 # Anonymous module for extending the proxy, see "Association extensions".
1158 # [:include]
1159 # Specify second-order associations that should be eager loaded when the collection is loaded.
1160 # [:group]
1161 # An attribute name by which the result should be grouped. Uses the <tt>GROUP BY</tt> SQL-clause.
97403ad5 » miloops 2008-11-21 Add :having option to find,... 1162 # [:having]
1163 # Combined with +:group+ this can be used to filter the records that a <tt>GROUP BY</tt> returns. Uses the <tt>HAVING</tt> SQL-clause.
6e754551 » lifo 2008-07-28 Merge docrails changes 1164 # [:limit]
1165 # An integer determining the limit on the number of rows that should be returned.
1166 # [:offset]
1167 # An integer determining the offset from where the rows should be fetched. So at 5, it would skip the first 4 rows.
1168 # [:select]
1169 # By default, this is <tt>*</tt> as in <tt>SELECT * FROM</tt>, but can be changed if, for example, you want to do a join
8d0b4fa3 » josevalim 2008-05-23 Added :select option to has... 1170 # but not include the joined columns. Do not forget to include the primary and foreign keys, otherwise it will raise an error.
6e754551 » lifo 2008-07-28 Merge docrails changes 1171 # [:readonly]
1172 # If true, all the associated objects are readonly through the association.
1173 # [:validate]
1174 # If false, don't validate the associated objects when saving the parent object. +true+ by default.
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1175 # [:autosave]
1176 # If true, always save any loaded members and destroy members marked for destruction, when saving the parent object. Off by default.
db045dbb » dhh 2004-11-23 Initial 1177 #
1178 # Option examples:
1179 # has_and_belongs_to_many :projects
49c801b7 » dhh 2005-11-06 Added :include as an option... 1180 # has_and_belongs_to_many :projects, :include => [ :milestones, :manager ]
db045dbb » dhh 2004-11-23 Initial 1181 # has_and_belongs_to_many :nations, :class_name => "Country"
1182 # has_and_belongs_to_many :categories, :join_table => "prods_cats"
dfa78663 » jeremy 2008-02-12 Introduce the :readonly opt... 1183 # has_and_belongs_to_many :categories, :readonly => true
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1184 # has_and_belongs_to_many :active_projects, :join_table => 'developers_projects', :delete_sql =>
190e0464 » dhh 2005-05-19 Fixed that :delete_sql in h... 1185 # 'DELETE FROM developers_projects WHERE active=1 AND developer_id = #{id} AND project_id = #{record.id}'
c8dd66fd » dhh 2005-11-06 Made association extensions... 1186 def has_and_belongs_to_many(association_id, options = {}, &extension)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1187 reflection = create_has_and_belongs_to_many_reflection(association_id, options, &extension)
1188 collection_accessor_methods(reflection, HasAndBelongsToManyAssociation)
db045dbb » dhh 2004-11-23 Initial 1189
35b4bdcf » jeremy 2005-11-08 Destroy associated has_and_... 1190 # Don't use a before_destroy callback since users' before_destroy
1191 # callbacks will be executed after the association is wiped out.
6abda696 » dhh 2005-12-02 Added preliminary support f... 1192 old_method = "destroy_without_habtm_shim_for_#{reflection.name}"
88f951a5 » jeremy 2007-10-27 Allow association redefinit... 1193 class_eval <<-end_eval unless method_defined?(old_method)
a2270ef2 » fxn 2008-12-28 Inline code comments for cl... Comment 1194 alias_method :#{old_method}, :destroy_without_callbacks # alias_method :destroy_without_habtm_shim_for_posts, :destroy_without_callbacks
1195 def destroy_without_callbacks # def destroy_without_callbacks
1196 #{reflection.name}.clear # posts.clear
1197 #{old_method} # destroy_without_habtm_shim_for_posts
1198 end # end
35b4bdcf » jeremy 2005-11-08 Destroy associated has_and_... 1199 end_eval
1200
6abda696 » dhh 2005-12-02 Added preliminary support f... 1201 add_association_callbacks(reflection.name, options)
db045dbb » dhh 2004-11-23 Initial 1202 end
1203
1204 private
6ef35461 » lifo 2008-09-03 Merge docrails 1205 # Generates a join table name from two provided table names.
1206 # The names in the join table namesme end up in lexicographic order.
1207 #
1208 # join_table_name("members", "clubs") # => "clubs_members"
1209 # join_table_name("members", "special_clubs") # => "members_special_clubs"
db045dbb » dhh 2004-11-23 Initial 1210 def join_table_name(first_table_name, second_table_name)
1211 if first_table_name < second_table_name
1212 join_table = "#{first_table_name}_#{second_table_name}"
1213 else
1214 join_table = "#{second_table_name}_#{first_table_name}"
1215 end
1216
1217 table_name_prefix + join_table + table_name_suffix
1218 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1219
6abda696 » dhh 2005-12-02 Added preliminary support f... 1220 def association_accessor_methods(reflection, association_proxy_class)
1221 define_method(reflection.name) do |*params|
823554ea » dhh 2005-01-15 Added support for associati... 1222 force_reload = params.first unless params.empty?
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1223 association = association_instance_get(reflection.name)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1224
cb45ee34 » NZKoz 2008-10-10 Remove the functionality in... 1225 if association.nil? || force_reload
6abda696 » dhh 2005-12-02 Added preliminary support f... 1226 association = association_proxy_class.new(self, reflection)
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1227 retval = association.reload
94a13091 » technoweenie 2006-08-08 Cache nil results for has_o... 1228 if retval.nil? and association_proxy_class == BelongsToAssociation
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1229 association_instance_set(reflection.name, nil)
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1230 return nil
1231 end
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1232 association_instance_set(reflection.name, association)
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1233 end
94a13091 » technoweenie 2006-08-08 Cache nil results for has_o... 1234
1235 association.target.nil? ? nil : association
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1236 end
1237
4c050554 » willbryant 2008-09-26 explicitly including child ... 1238 define_method("loaded_#{reflection.name}?") do
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1239 association = association_instance_get(reflection.name)
4c050554 » willbryant 2008-09-26 explicitly including child ... 1240 association && association.loaded?
1241 end
1242
6abda696 » dhh 2005-12-02 Added preliminary support f... 1243 define_method("#{reflection.name}=") do |new_value|
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1244 association = association_instance_get(reflection.name)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1245
4afd6c9f » jeremy 2007-05-21 belongs_to assignment creat... 1246 if association.nil? || association.target != new_value
6abda696 » dhh 2005-12-02 Added preliminary support f... 1247 association = association_proxy_class.new(self, reflection)
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1248 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1249
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 1250 if association_proxy_class == HasOneThroughAssociation
1251 association.create_through_record(new_value)
1252 self.send(reflection.name, new_value)
1253 else
9dbde4f5 » pivotal 2008-08-26 Fix two has_one :through er... 1254 association.replace(new_value)
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1255 association_instance_set(reflection.name, new_value.nil? ? nil : association)
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 1256 end
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1257 end
f8783abf » dhh 2005-04-03 Made eager loading work eve... 1258
6abda696 » dhh 2005-12-02 Added preliminary support f... 1259 define_method("set_#{reflection.name}_target") do |target|
18057d2f » jeremy 2006-08-17 Cache nil results for :incl... 1260 return if target.nil? and association_proxy_class == BelongsToAssociation
6abda696 » dhh 2005-12-02 Added preliminary support f... 1261 association = association_proxy_class.new(self, reflection)
f8783abf » dhh 2005-04-03 Made eager loading work eve... 1262 association.target = target
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1263 association_instance_set(reflection.name, association)
f8783abf » dhh 2005-04-03 Made eager loading work eve... 1264 end
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1265 end
1266
6abda696 » dhh 2005-12-02 Added preliminary support f... 1267 def collection_reader_method(reflection, association_proxy_class)
1268 define_method(reflection.name) do |*params|
bce0e149 » dhh 2005-01-18 Fixed that the belongs_to a... 1269 force_reload = params.first unless params.empty?
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1270 association = association_instance_get(reflection.name)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1271
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1272 unless association
6abda696 » dhh 2005-12-02 Added preliminary support f... 1273 association = association_proxy_class.new(self, reflection)
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1274 association_instance_set(reflection.name, association)
db045dbb » dhh 2004-11-23 Initial 1275 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1276
823554ea » dhh 2005-01-15 Added support for associati... 1277 association.reload if force_reload
6abda696 » dhh 2005-12-02 Added preliminary support f... 1278
823554ea » dhh 2005-01-15 Added support for associati... 1279 association
1280 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1281
1282 define_method("#{reflection.name.to_s.singularize}_ids") do
838cb1aa » jeremy 2008-10-23 Skip collection ids reader ... 1283 if send(reflection.name).loaded? || reflection.options[:finder_sql]
b163d83b » miloops 2008-08-30 Performance: Better query f... 1284 send(reflection.name).map(&:id)
1285 else
6183e55f » miloops 2008-08-30 Use reflection primary_key ... 1286 send(reflection.name).all(:select => "#{reflection.quoted_table_name}.#{reflection.klass.primary_key}").map(&:id)
b163d83b » miloops 2008-08-30 Performance: Better query f... 1287 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1288 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1289 end
db045dbb » dhh 2004-11-23 Initial 1290
b5b16a80 » jeremy 2007-06-27 Define collection singular ... 1291 def collection_accessor_methods(reflection, association_proxy_class, writer = true)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1292 collection_reader_method(reflection, association_proxy_class)
1293
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1294 if writer
1295 define_method("#{reflection.name}=") do |new_value|
1296 # Loads proxy class instance (defined in collection_reader_method) if not already loaded
1297 association = send(reflection.name)
1298 association.replace(new_value)
1299 association
1300 end
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 1301
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1302 define_method("#{reflection.name.to_s.singularize}_ids=") do |new_value|
1303 ids = (new_value || []).reject { |nid| nid.blank? }
1304 send("#{reflection.name}=", reflection.class_name.constantize.find(ids))
1305 end
0092d0ac » jeremy 2006-10-01 Association collections hav... 1306 end
db045dbb » dhh 2004-11-23 Initial 1307 end
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1308
6abda696 » dhh 2005-12-02 Added preliminary support f... 1309 def association_constructor_method(constructor, reflection, association_proxy_class)
1310 define_method("#{constructor}_#{reflection.name}") do |*params|
2bdaff4a » dhh 2005-06-06 Added a second parameter to... 1311 attributees = params.first unless params.empty?
1312 replace_existing = params[1].nil? ? true : params[1]
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1313 association = association_instance_get(reflection.name)
3b9e90a4 » dhh 2005-04-11 Moved build_association and... 1314
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1315 unless association
6abda696 » dhh 2005-12-02 Added preliminary support f... 1316 association = association_proxy_class.new(self, reflection)
ec8f0458 » alloy 2009-01-31 Add support for nested obje... Comment 1317 association_instance_set(reflection.name, association)
3b9e90a4 » dhh 2005-04-11 Moved build_association and... 1318 end
1319
bfe6a759 » dhh 2005-06-15 Added actual database-chang... 1320 if association_proxy_class == HasOneAssociation
1321 association.send(constructor, attributees, replace_existing)
1322 else
1323 association.send(constructor, attributees)
1324 end
3b9e90a4 » dhh 2005-04-11 Moved build_association and... 1325 end
1326 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1327
abc895b8 » dhh 2005-04-03 Added new Base.find API and... 1328 def find_with_associations(options = {})
31d8169e » technoweenie 2006-04-05 Fixed that loading includin... 1329 catch :invalid_query do
37adea6f » dhh 2007-11-07 Address shortcomings of cha... 1330 join_dependency = JoinDependency.new(self, merge_includes(scope(:find, :include), options[:include]), options[:joins])
31d8169e » technoweenie 2006-04-05 Fixed that loading includin... 1331 rows = select_all_rows(options, join_dependency)
1332 return join_dependency.instantiate(rows)
1333 end
1334 []
3a7be80f » dhh 2006-03-15 Change LEFT OUTER JOIN auth... 1335 end
6f344000 » dhh 2005-04-19 Fixed order of loading in e... 1336
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1337 # Creates before_destroy callback methods that nullify, delete or destroy
1338 # has_many associated objects, according to the defined :dependent rule.
1339 #
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1340 # See HasManyAssociation#delete_records. Dependent associations
1341 # delete children, otherwise foreign key is set to NULL.
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1342 #
1343 # The +extra_conditions+ parameter, which is not used within the main
1344 # Active Record codebase, is meant to allow plugins to define extra
1345 # finder conditions.
1346 def configure_dependency_for_has_many(reflection, extra_conditions = nil)
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1347 if reflection.options.include?(:dependent)
1348 # Add polymorphic type if the :as option is present
1349 dependent_conditions = []
1350 dependent_conditions << "#{reflection.primary_key_name} = \#{record.quoted_id}"
1351 dependent_conditions << "#{reflection.options[:as]}_type = '#{base_class.name}'" if reflection.options[:as]
1352 dependent_conditions << sanitize_sql(reflection.options[:conditions]) if reflection.options[:conditions]
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1353 dependent_conditions << extra_conditions if extra_conditions
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1354 dependent_conditions = dependent_conditions.collect {|where| "(#{where})" }.join(" AND ")
b17b9371 » fcheung 2008-12-21 Fix configure_dependency_fo... 1355 dependent_conditions = dependent_conditions.gsub('@', '\@')
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1356 case reflection.options[:dependent]
1357 when :destroy
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1358 method_name = "has_many_dependent_destroy_for_#{reflection.name}".to_sym
1359 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1360 send(reflection.name).each { |o| o.destroy }
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1361 end
1362 before_destroy method_name
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1363 when :delete_all
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1364 module_eval %Q{
a2270ef2 » fxn 2008-12-28 Inline code comments for cl... Comment 1365 before_destroy do |record| # before_destroy do |record|
1366 delete_all_has_many_dependencies(record, # delete_all_has_many_dependencies(record,
1367 "#{reflection.name}", # "posts",
1368 #{reflection.class_name}, # Post,
1369 %@#{dependent_conditions}@) # %@...@) # this is a string literal like %(...)
1370 end # end
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1371 }
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1372 when :nullify
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1373 module_eval %Q{
a2270ef2 » fxn 2008-12-28 Inline code comments for cl... Comment 1374 before_destroy do |record| # before_destroy do |record|
1375 nullify_has_many_dependencies(record, # nullify_has_many_dependencies(record,
1376 "#{reflection.name}", # "posts",
1377 #{reflection.class_name}, # Post,
1378 "#{reflection.primary_key_name}", # "user_id",
1379 %@#{dependent_conditions}@) # %@...@) # this is a string literal like %(...)
1380 end # end
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1381 }
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1382 else
1383 raise ArgumentError, "The :dependent option expects either :destroy, :delete_all, or :nullify (#{reflection.options[:dependent].inspect})"
1384 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1385 end
1386 end
3f1acf49 » jeremy 2006-09-15 Deprecation tests. Remove w... 1387
a2932784 » lifo 2008-10-05 Merge docrails 1388 # Creates before_destroy callback methods that nullify, delete or destroy
1389 # has_one associated objects, according to the defined :dependent rule.
6abda696 » dhh 2005-12-02 Added preliminary support f... 1390 def configure_dependency_for_has_one(reflection)
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1391 if reflection.options.include?(:dependent)
1392 case reflection.options[:dependent]
1393 when :destroy
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1394 method_name = "has_one_dependent_destroy_for_#{reflection.name}".to_sym
1395 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1396 association = send(reflection.name)
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1397 association.destroy unless association.nil?
1398 end
1399 before_destroy method_name
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1400 when :delete
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1401 method_name = "has_one_dependent_delete_for_#{reflection.name}".to_sym
1402 define_method(method_name) do
a2932784 » lifo 2008-10-05 Merge docrails 1403 # Retrieve the associated object and delete it. The retrieval
1404 # is necessary because there may be multiple associated objects
1405 # with foreign keys pointing to this object, and we only want
1406 # to delete the correct one, not all of them.
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1407 association = send(reflection.name)
46939a9b » Hongli Lai (Phusion 2008-09-21 Add Model#delete instance m... Comment 1408 association.delete unless association.nil?
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1409 end
1410 before_destroy method_name
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1411 when :nullify
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1412 method_name = "has_one_dependent_nullify_for_#{reflection.name}".to_sym
1413 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1414 association = send(reflection.name)
1415 association.update_attribute(reflection.primary_key_name, nil) unless association.nil?
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1416 end
1417 before_destroy method_name
aa04635d » jeremy 2007-10-08 Update :dependent docs and ... 1418 else
1419 raise ArgumentError, "The :dependent option expects either :destroy, :delete or :nullify (#{reflection.options[:dependent].inspect})"
1420 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1421 end
1422 end
1423
16b129a6 » jeremy 2008-01-18 belongs_to supports :depend... 1424 def configure_dependency_for_belongs_to(reflection)
1425 if reflection.options.include?(:dependent)
1426 case reflection.options[:dependent]
1427 when :destroy
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1428 method_name = "belongs_to_dependent_destroy_for_#{reflection.name}".to_sym
1429 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1430 association = send(reflection.name)
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1431 association.destroy unless association.nil?
1432 end
0e92f670 » bvandenbos 2009-01-05 Make belongs_to :dependent ... 1433 after_destroy method_name
16b129a6 » jeremy 2008-01-18 belongs_to supports :depend... 1434 when :delete
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1435 method_name = "belongs_to_dependent_delete_for_#{reflection.name}".to_sym
1436 define_method(method_name) do
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1437 association = send(reflection.name)
46939a9b » Hongli Lai (Phusion 2008-09-21 Add Model#delete instance m... Comment 1438 association.delete unless association.nil?
de048b10 » technoweenie 2008-02-13 Improve associations perfor... 1439 end
0e92f670 » bvandenbos 2009-01-05 Make belongs_to :dependent ... 1440 after_destroy method_name
16b129a6 » jeremy 2008-01-18 belongs_to supports :depend... 1441 else
1442 raise ArgumentError, "The :dependent option expects either :destroy or :delete (#{reflection.options[:dependent].inspect})"
1443 end
1444 end
1445 end
1446
72b772ae » Hongli Lai (Phusion) 2008-09-21 Refactor configure_dependen... 1447 def delete_all_has_many_dependencies(record, reflection_name, association_class, dependent_conditions)
1448 association_class.delete_all(dependent_conditions)
1449 end
1450
1451 def nullify_has_many_dependencies(record, reflection_name, association_class, primary_key_name, dependent_conditions)
1452 association_class.update_all("#{primary_key_name} = NULL", dependent_conditions)
1453 end
1454
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1455 mattr_accessor :valid_keys_for_has_many_association
1456 @@valid_keys_for_has_many_association = [
1457 :class_name, :table_name, :foreign_key, :primary_key,
1458 :dependent,
97403ad5 » miloops 2008-11-21 Add :having option to find,... 1459 :select, :conditions, :include, :order, :group, :having, :limit, :offset,
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1460 :as, :through, :source, :source_type,
1461 :uniq,
1462 :finder_sql, :counter_sql,
1463 :before_add, :after_add, :before_remove, :after_remove,
1464 :extend, :readonly,
9994f0d9 » lifo 2008-09-10 Revert "Add :accessible opt... Comment 1465 :validate
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1466 ]
1467
6abda696 » dhh 2005-12-02 Added preliminary support f... 1468 def create_has_many_reflection(association_id, options, &extension)
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1469 options.assert_valid_keys(valid_keys_for_has_many_association)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1470 options[:extend] = create_extension_modules(association_id, extension, options[:extend])
6abda696 » dhh 2005-12-02 Added preliminary support f... 1471
8203a2af » dhh 2006-02-26 Dont require association cl... 1472 create_reflection(:has_many, association_id, options, self)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1473 end
1474
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1475 mattr_accessor :valid_keys_for_has_one_association
1476 @@valid_keys_for_has_one_association = [
1477 :class_name, :foreign_key, :remote, :select, :conditions, :order,
1478 :include, :dependent, :counter_cache, :extend, :as, :readonly,
9994f0d9 » lifo 2008-09-10 Revert "Add :accessible opt... Comment 1479 :validate, :primary_key
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1480 ]
1481
6abda696 » dhh 2005-12-02 Added preliminary support f... 1482 def create_has_one_reflection(association_id, options)
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1483 options.assert_valid_keys(valid_keys_for_has_one_association)
8203a2af » dhh 2006-02-26 Dont require association cl... 1484 create_reflection(:has_one, association_id, options, self)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1485 end
ba3ecf53 » clemens 2008-09-02 Some performance goodness f... 1486
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 1487 def create_has_one_through_reflection(association_id, options)
1488 options.assert_valid_keys(
7f140bbd » DefV 2008-06-11 Add :validate option to ass... 1489 :class_name, :foreign_key, :remote, :select, :conditions, :order, :include, :dependent, :counter_cache, :extend, :as, :through, :source, :source_type, :validate
273b21fa » technoweenie 2008-03-21 Add has_one :through suppor... 1490 )
1491 create_reflection(:has_one, association_id, options, self)
1492 end
6abda696 » dhh 2005-12-02 Added preliminary support f... 1493
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1494 mattr_accessor :valid_keys_for_belongs_to_association
1495 @@valid_keys_for_belongs_to_association = [
1496 :class_name, :foreign_key, :foreign_type, :remote, :select, :conditions,
1497 :include, :dependent, :counter_cache, :extend, :polymorphic, :readonly,
9994f0d9 » lifo 2008-09-10 Revert "Add :accessible opt... Comment 1498 :validate
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1499 ]
1500
6abda696 » dhh 2005-12-02 Added preliminary support f... 1501 def create_belongs_to_reflection(association_id, options)
16929404 » Hongli Lai (Phusion) 2008-09-06 Make the options that has_m... 1502 options.assert_valid_keys(valid_keys_for_belongs_to_association)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1503 reflection = create_reflection(:belongs_to, association_id, options, self)
1504
1505 if options[:polymorphic]
1506 reflection.options[:foreign_type] ||= reflection.class_name.underscore + "_type"
1507 end
1508
1509 reflection
1510 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1511
5229fc4c » jodosha 2008-10-31 Make sure habtm use class v... 1512 mattr_accessor :valid_keys_for_has_and_belongs_to_many_association
1513 @@valid_keys_for_has_and_belongs_to_many_association = [
1514 :class_name, :table_name, :join_table, :foreign_key, :association_foreign_key,
97403ad5 » miloops 2008-11-21 Add :having option to find,... 1515 :select, :conditions, :include, :order, :group, :having, :limit, :offset,
5229fc4c » jodosha 2008-10-31 Make sure habtm use class v... 1516 :uniq,
26978e3c » tekin 2008-11-06 Added :counter_sql as a val... 1517 :finder_sql, :counter_sql, :delete_sql, :insert_sql,
5229fc4c » jodosha 2008-10-31 Make sure habtm use class v... 1518 :before_add, :after_add, :before_remove, :after_remove,
1519 :extend, :readonly,
1520 :validate
1521 ]
1522
6abda696 » dhh 2005-12-02 Added preliminary support f... 1523 def create_has_and_belongs_to_many_reflection(association_id, options, &extension)
5229fc4c » jodosha 2008-10-31 Make sure habtm use class v... 1524 options.assert_valid_keys(valid_keys_for_has_and_belongs_to_many_association)
6abda696 » dhh 2005-12-02 Added preliminary support f... 1525
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1526 options[:extend] = create_extension_modules(association_id, extension, options[:extend])
6abda696 » dhh 2005-12-02 Added preliminary support f... 1527
1528 reflection = create_reflection(:has_and_belongs_to_many, association_id, options, self)
1529
1530 reflection.options[:join_table] ||= join_table_name(undecorated_table_name(self.to_s), undecorated_table_name(reflection.class_name))
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1531
6abda696 » dhh 2005-12-02 Added preliminary support f... 1532 reflection
1533 end
1534
49d0f0cb » dhh 2005-04-18 Speeded up eager loading a ... 1535 def reflect_on_included_associations(associations)
251a5d45 » seckar 2005-09-18 Fix eager loading error mes... 1536 [ associations ].flatten.collect { |association| reflect_on_association(association.to_s.intern) }
49d0f0cb » dhh 2005-04-18 Speeded up eager loading a ... 1537 end
1538
5b9b904f » dhh 2005-07-10 Added support for limit and... 1539 def guard_against_unlimitable_reflections(reflections, options)
1540 if (options[:offset] || options[:limit]) && !using_limitable_reflections?(reflections)
1541 raise(
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1542 ConfigurationError,
5b9b904f » dhh 2005-07-10 Added support for limit and... 1543 "You can not use offset and limit together with has_many or has_and_belongs_to_many associations"
1544 )
1545 end
1546 end
1547
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1548 def select_all_rows(options, join_dependency)
49d0f0cb » dhh 2005-04-18 Speeded up eager loading a ... 1549 connection.select_all(
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1550 construct_finder_sql_with_included_associations(options, join_dependency),
49d0f0cb » dhh 2005-04-18 Speeded up eager loading a ... 1551 "#{name} Load Including Associations"
1552 )
1553 end
057cf491 » dhh 2005-04-10 Added support for has_and_b... 1554
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1555 def construct_finder_sql_with_included_associations(options, join_dependency)
c9c18520 » dhh 2006-03-27 Making ActiveRecord faster ... 1556 scope = scope(:find)
a5fded3e » dhh 2007-12-04 Fix that options[:from] tab... 1557 sql = "SELECT #{column_aliases(join_dependency)} FROM #{(scope && scope[:from]) || options[:from] || quoted_table_name} "
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1558 sql << join_dependency.join_associations.collect{|join| join.association_join }.join
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1559
db22c895 » pixeltrix 2008-08-28 Merge scoped :joins togethe... 1560 add_joins!(sql, options[:joins], scope)
c9c18520 » dhh 2006-03-27 Making ActiveRecord faster ... 1561 add_conditions!(sql, options[:conditions], scope)
d016d9a6 » dhh 2006-06-03 Fixed usage of :limit and w... 1562 add_limited_ids_condition!(sql, options, join_dependency) if !using_limitable_reflections?(join_dependency.reflections) && ((scope && scope[:limit]) || options[:limit])
851dd080 » dhh 2005-10-18 Added support for using lim... 1563
97403ad5 » miloops 2008-11-21 Add :having option to find,... 1564 add_group!(sql, options[:group], options[:having], scope)
9d2da046 » jeremy 2006-11-09 Cache inheritance_column. C... 1565 add_order!(sql, options[:order], scope)
c9c18520 » dhh 2006-03-27 Making ActiveRecord faster ... 1566 add_limit!(sql, options, scope) if using_limitable_reflections?(join_dependency.reflections)
8dea60b0 » jeremy 2006-12-05 find supports :lock with :i... 1567 add_lock!(sql, options, scope)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1568
abc895b8 » dhh 2005-04-03 Added new Base.find API and... 1569 return sanitize_sql(sql)
1570 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1571
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1572 def add_limited_ids_condition!(sql, options, join_dependency)
1573 unless (id_list = select_limited_ids_list(options, join_dependency)).empty?
79823e0b » NZKoz 2007-11-10 Ensure that column names ar... 1574 sql << "#{condition_word(sql)} #{connection.quote_table_name table_name}.#{primary_key} IN (#{id_list}) "
31d8169e » technoweenie 2006-04-05 Fixed that loading includin... 1575 else
1576 throw :invalid_query
851dd080 » dhh 2005-10-18 Added support for using lim... 1577 end
1578 end
4965b1b9 » jeremy 2007-09-22 Correctly quote id list for... 1579
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1580 def select_limited_ids_list(options, join_dependency)
4965b1b9 » jeremy 2007-09-22 Correctly quote id list for... 1581 pk = columns_hash[primary_key]
1582
5ea76fab » technoweenie 2006-04-18 Associations#select_limited... 1583 connection.select_all(
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1584 construct_finder_sql_for_association_limiting(options, join_dependency),
851dd080 » dhh 2005-10-18 Added support for using lim... 1585 "#{name} Load IDs For Limited Eager Loading"
4965b1b9 » jeremy 2007-09-22 Correctly quote id list for... 1586 ).collect { |row| connection.quote(row[primary_key], pk) }.join(", ")
851dd080 » dhh 2005-10-18 Added support for using lim... 1587 end
c0bce43e » jeremy 2006-11-10 Oracle: fix limited id sele... 1588
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1589 def construct_finder_sql_for_association_limiting(options, join_dependency)
e789b26e » technoweenie 2006-10-13 fix select_limited_ids_list... 1590 scope = scope(:find)
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1591
1592 # Only join tables referenced in order or conditions since this is particularly slow on the pre-query.
1593 tables_from_conditions = conditions_tables(options)
1594 tables_from_order = order_tables(options)
1595 all_tables = tables_from_conditions + tables_from_order
8ded457b » jdevine 2008-05-03 Added logic to associations... 1596 distinct_join_associations = all_tables.uniq.map{|table|
1597 join_dependency.joins_for_table_name(table)
1598 }.flatten.compact.uniq
1599
8c91b767 » tarmo 2008-07-14 Fixed postgresql limited ea... 1600 order = options[:order]
1601 if scoped_order = (scope && scope[:order])
1602 order = order ? "#{order}, #{scoped_order}" : scoped_order
1603 end
1604
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1605 is_distinct = !options[:joins].blank? || include_eager_conditions?(options, tables_from_conditions) || include_eager_order?(options, tables_from_order)
d49a5fcb » NZKoz 2006-02-09 * Fix pagination problems w... 1606 sql = "SELECT "
e789b26e » technoweenie 2006-10-13 fix select_limited_ids_list... 1607 if is_distinct
8c91b767 » tarmo 2008-07-14 Fixed postgresql limited ea... 1608 sql << connection.distinct("#{connection.quote_table_name table_name}.#{primary_key}", order)
e789b26e » technoweenie 2006-10-13 fix select_limited_ids_list... 1609 else
1610 sql << primary_key
1611 end
79823e0b » NZKoz 2007-11-10 Ensure that column names ar... 1612 sql << " FROM #{connection.quote_table_name table_name} "
c0bce43e » jeremy 2006-11-10 Oracle: fix limited id sele... 1613
e789b26e » technoweenie 2006-10-13 fix select_limited_ids_list... 1614 if is_distinct
ce4a1bb8 » chuyeow 2008-06-25 Remove some Symbol#to_proc ... Comment 1615 sql << distinct_join_associations.collect { |assoc| assoc.association_join }.join
db22c895 » pixeltrix 2008-08-28 Merge scoped :joins togethe... 1616 add_joins!(sql, options[:joins], scope)
d49a5fcb » NZKoz 2006-02-09 * Fix pagination problems w... 1617 end
c0bce43e » jeremy 2006-11-10 Oracle: fix limited id sele... 1618
c9c18520 » dhh 2006-03-27 Making ActiveRecord faster ... 1619 add_conditions!(sql, options[:conditions], scope)
97403ad5 » miloops 2008-11-21 Add :having option to find,... 1620 add_group!(sql, options[:group], options[:having], scope)
0e452bb0 » dhh 2007-08-21 Fixed that eager loading qu... 1621
8c91b767 » tarmo 2008-07-14 Fixed postgresql limited ea... 1622 if order && is_distinct
1623 connection.add_order_by_for_association_limiting!(sql, :order => order)
c8b6b482 » Marcel Molina 2007-10-23 Limited eager loading no lo... 1624 else
1625 add_order!(sql, options[:order], scope)
ef4ac31d » jeremy 2007-01-11 PostgreSQL: use a subselect... 1626 end
0e452bb0 » dhh 2007-08-21 Fixed that eager loading qu... 1627
c9c18520 » dhh 2006-03-27 Making ActiveRecord faster ... 1628 add_limit!(sql, options, scope)
0e452bb0 » dhh 2007-08-21 Fixed that eager loading qu... 1629
851dd080 » dhh 2005-10-18 Added support for using lim... 1630 return sanitize_sql(sql)
1631 end
c98b471c » technoweenie 2006-10-08 Reverted old select_limited... 1632
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1633 def tables_in_string(string)
1634 return [] if string.blank?
1635 string.scan(/([\.a-zA-Z_]+).?\./).flatten
1636 end
1637
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1638 def conditions_tables(options)
2a2afca0 » technoweenie 2006-04-19 Ensure that Associations#in... 1639 # look in both sets of conditions
1640 conditions = [scope(:find, :conditions), options[:conditions]].inject([]) do |all, cond|
1641 case cond
1642 when nil then all
1643 when Array then all << cond.first
9a4d5577 » Paul 2008-11-26 Ensure hash conditions on r... 1644 when Hash then all << cond.keys
2a2afca0 » technoweenie 2006-04-19 Ensure that Associations#in... 1645 else all << cond
1646 end
1647 end
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1648 tables_in_string(conditions.join(' '))
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1649 end
1650
1651 def order_tables(options)
e94e53f9 » brandon 2008-06-09 fix eager loading with dyna... 1652 order = [options[:order], scope(:find, :order) ].join(", ")
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1653 return [] unless order && order.is_a?(String)
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1654 tables_in_string(order)
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1655 end
1656
b28b54ca » jdevine 2008-05-04 Make sure needed table join... 1657 def selects_tables(options)
1658 select = options[:select]
1659 return [] unless select && select.is_a?(String)
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1660 tables_in_string(select)
1661 end
1662
1663 def joined_tables(options)
1664 scope = scope(:find)
1665 joins = options[:joins]
1666 merged_joins = scope && scope[:joins] && joins ? merge_joins(scope[:joins], joins) : (joins || scope && scope[:joins])
1667 [table_name] + case merged_joins
1668 when Symbol, Hash, Array
1669 if array_of_strings?(merged_joins)
1670 tables_in_string(merged_joins.join(' '))
1671 else
1672 join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, merged_joins, nil)
9c7fe7c6 » fcheung 2008-12-18 Don't include table_name twice 1673 join_dependency.join_associations.collect {|join_association| [join_association.aliased_join_table_name, join_association.aliased_table_name]}.flatten.compact
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1674 end
1675 else
1676 tables_in_string(merged_joins)
1677 end
b28b54ca » jdevine 2008-05-04 Make sure needed table join... 1678 end
1679
4ca170fc » NZKoz 2008-03-02 Improve performance on :inc... 1680 # Checks if the conditions reference a table other than the current model table
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1681 def include_eager_conditions?(options, tables = nil, joined_tables = nil)
1682 ((tables || conditions_tables(options)) - (joined_tables || joined_tables(options))).any?
851dd080 » dhh 2005-10-18 Added support for using lim... 1683 end
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1684
2a2afca0 » technoweenie 2006-04-19 Ensure that Associations#in... 1685 # Checks if the query order references a table other than the current model's table.
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1686 def include_eager_order?(options, tables = nil, joined_tables = nil)
1687 ((tables || order_tables(options)) - (joined_tables || joined_tables(options))).any?
d49a5fcb » NZKoz 2006-02-09 * Fix pagination problems w... 1688 end
851dd080 » dhh 2005-10-18 Added support for using lim... 1689
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1690 def include_eager_select?(options, joined_tables = nil)
1691 (selects_tables(options) - (joined_tables || joined_tables(options))).any?
b28b54ca » jdevine 2008-05-04 Make sure needed table join... 1692 end
1693
355a8ff2 » jeremy 2008-01-18 Introduce preload query str... 1694 def references_eager_loaded_tables?(options)
c9ab7098 » fcheung 2008-12-18 Ensure :include checks join... 1695 joined_tables = joined_tables(options)
1696 include_eager_order?(options, nil, joined_tables) || include_eager_conditions?(options, nil, joined_tables) || include_eager_select?(options, joined_tables)
355a8ff2 » jeremy 2008-01-18 Introduce preload query str... 1697 end
1698
5b9b904f » dhh 2005-07-10 Added support for limit and... 1699 def using_limitable_reflections?(reflections)
1700 reflections.reject { |r| [ :belongs_to, :has_one ].include?(r.macro) }.length.zero?
1701 end
1702
55854c41 » dhh 2006-03-04 Added cascading eager loadi... 1703 def column_aliases(join_dependency)
1704 join_dependency.joins.collect{|join| join.column_names_with_alias.collect{|column_name, aliased_name|
79823e0b » NZKoz 2007-11-10 Ensure that column names ar... 1705 "#{connection.quote_table_name join.aliased_table_name}.#{connection.quote_column_name column_name} AS #{aliased_name}"}}.flatten.join(", ")
057cf491 » dhh 2005-04-10 Added support for has_and_b... 1706 end
1707
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 1708 def add_association_callbacks(association_name, options)
e19bd169 » jeremy 2005-10-01 Association validation does... 1709 callbacks = %w(before_add after_add before_remove after_remove)
1710 callbacks.each do |callback_name|
7cc446ac » Marcel Molina 2006-04-15 DRY up association collecti... 1711 full_callback_name = "#{callback_name}_for_#{association_name}"
e19bd169 » jeremy 2005-10-01 Association validation does... 1712 defined_callbacks = options[callback_name.to_sym]
1713 if options.has_key?(callback_name.to_sym)
1714 class_inheritable_reader full_callback_name.to_sym
88f951a5 » jeremy 2007-10-27 Allow association redefinit... 1715 write_inheritable_attribute(full_callback_name.to_sym, [defined_callbacks].flatten)
1716 else
1717 write_inheritable_attribute(full_callback_name.to_sym, [])
e19bd169 » jeremy 2005-10-01 Association validation does... 1718 end
1719 end
4180e57b » dhh 2005-07-04 Added callback hooks to ass... 1720 end
057cf491 » dhh 2005-04-10 Added support for has_and_b... 1721
851dd080 » dhh 2005-10-18 Added support for using lim... 1722 def condition_word(sql)
1723 sql =~ /where/i ? " AND " : "WHERE "
1724 end
e19bd169 » jeremy 2005-10-01 Association validation does... 1725
81d619ea » jeremy 2007-09-17 Associations macros accept ... 1726 def create_extension_modules(association_id, block_extension, extensions)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1727 if block_extension
de96a866 » adevadeh 2008-09-12 applied patch to fix the as... 1728 extension_module_name = "#{self.to_s.demodulize}#{association_id.to_s.camelize}AssociationExtension"
c8dd66fd » dhh 2005-11-06 Made association extensions... 1729
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1730 silence_warnings do
de96a866 » adevadeh 2008-09-12 applied patch to fix the as... 1731 self.parent.const_set(extension_module_name, Module.new(&block_extension))
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1732 end
de96a866 » adevadeh 2008-09-12 applied patch to fix the as... 1733 Array(extensions).push("#{self.parent}::#{extension_module_name}".constantize)
8b5f4e47 » jeremy 2007-12-22 Ruby 1.9 compat: fix warnin... 1734 else