Sequel::Model::Associations::ManyToManyAssociationReflection

Constants

FINALIZE_SETTINGS = superclass::FINALIZE_SETTINGS.merge( :associated_key_array=>:associated_key_array, :qualified_right_key=>:qualified_right_key, :join_table_source=>:join_table_source, :join_table_alias=>:join_table_alias, :qualified_right_primary_key=>:qualified_right_primary_key, :right_primary_key=>:right_primary_key, :right_primary_keys=>:right_primary_keys, :right_primary_key_method=>:right_primary_key_method, :right_primary_key_methods=>:right_primary_key_methods, :select=>:select ).freeze

Public Instance Aliases

associated_key_table	->	join_table_alias
qualified_left_key	->	predicate_key

Public Instance methods

associated_key_alias()

The alias to use for the associated key when eagerly loading

     # File lib/sequel/model/associations.rb
1241 def associated_key_alias
1242   self[:left_key_alias]
1243 end

associated_key_array()

Array of associated keys used when eagerly loading.

     # File lib/sequel/model/associations.rb
1246 def associated_key_array
1247   cached_fetch(:associated_key_array) do
1248     if self[:uses_left_composite_keys]
1249       associated_key_alias.zip(predicate_keys).map{|a, k| SQL::AliasedExpression.new(k, a)}
1250     else
1251       [SQL::AliasedExpression.new(predicate_key, associated_key_alias)]
1252     end
1253   end
1254 end

associated_key_column()

The column to use for the associated key when eagerly loading

     # File lib/sequel/model/associations.rb
1257 def associated_key_column
1258   self[:left_key]
1259 end

associated_object_keys()

Alias of right_primary_keys

     # File lib/sequel/model/associations.rb
1262 def associated_object_keys
1263   right_primary_keys
1264 end

can_have_associated_objects?(obj)

many_to_many associations can only have associated objects if none of the :left_primary_keys options have a nil value.

     # File lib/sequel/model/associations.rb
1268 def can_have_associated_objects?(obj)
1269   !self[:left_primary_keys].any?{|k| obj.get_column_value(k).nil?}
1270 end

cloneable?(ref)

one_through_one and many_to_many associations can be clones

     # File lib/sequel/model/associations.rb
1273 def cloneable?(ref)
1274   ref[:type] == :many_to_many || ref[:type] == :one_through_one
1275 end

default_associated_key_alias()

The default associated key alias(es) to use when eager loading associations via eager.

     # File lib/sequel/model/associations.rb
1279 def default_associated_key_alias
1280   self[:uses_left_composite_keys] ? (0...self[:left_keys].length).map{|i| :"x_foreign_key_#{i}_x"} : :x_foreign_key_x
1281 end

default_eager_loader(eo)

The default eager loader used if the user doesn’t override it. Extracted to a method so the code can be shared with the many_through_many plugin.

     # File lib/sequel/model/associations.rb
1285 def default_eager_loader(eo)
1286   h = eo[:id_map]
1287   assign_singular = assign_singular?
1288   delete_rn = delete_row_number_column
1289   uses_lcks = self[:uses_left_composite_keys]
1290   left_key_alias = self[:left_key_alias]
1291   name = self[:name]
1292 
1293   self[:model].eager_load_results(self, eo) do |assoc_record|
1294     assoc_record.values.delete(delete_rn) if delete_rn
1295     hash_key = if uses_lcks
1296       left_key_alias.map{|k| assoc_record.values.delete(k)}
1297     else
1298       assoc_record.values.delete(left_key_alias)
1299     end
1300 
1301     objects = h[hash_key]
1302 
1303     if assign_singular
1304       objects.each do |object| 
1305         object.associations[name] ||= assoc_record
1306       end
1307     else
1308       objects.each do |object|
1309         object.associations[name].push(assoc_record)
1310       end
1311     end
1312   end
1313 end

default_join_table()

Default name symbol for the join table.

     # File lib/sequel/model/associations.rb
1316 def default_join_table
1317   [self[:class_name], self[:model].name].map{|i| underscore(pluralize(demodulize(i)))}.sort.join('_').to_sym
1318 end

default_left_key()

Default foreign key name symbol for key in join table that points to current table’s primary key (or :left_primary_key column).

     # File lib/sequel/model/associations.rb
1322 def default_left_key
1323   :"#{underscore(demodulize(self[:model].name))}_id"
1324 end

default_right_key()

Default foreign key name symbol for foreign key in join table that points to the association’s table’s primary key (or :right_primary_key column).

     # File lib/sequel/model/associations.rb
1328 def default_right_key
1329   :"#{singularize(self[:name])}_id"
1330 end

eager_loading_use_associated_key?()

many_to_many associations need to select a key in an associated table to eagerly load

     # File lib/sequel/model/associations.rb
1361 def eager_loading_use_associated_key?
1362   !separate_query_per_table?
1363 end

finalize_settings()

     # File lib/sequel/model/associations.rb
1344 def finalize_settings
1345   FINALIZE_SETTINGS
1346 end

join_table_alias()

The join table itself, unless it is aliased, in which case this is the alias.

     # File lib/sequel/model/associations.rb
1373 def join_table_alias
1374   cached_fetch(:join_table_alias) do
1375     s, a = split_join_table_alias
1376     a || s
1377   end
1378 end

join_table_source()

The source of the join table. This is the join table itself, unless it is aliased, in which case it is the unaliased part.

     # File lib/sequel/model/associations.rb
1367 def join_table_source
1368   cached_fetch(:join_table_source){split_join_table_alias[0]}
1369 end

need_associated_primary_key?()

Whether the associated object needs a primary key to be added/removed, true for many_to_many associations.

     # File lib/sequel/model/associations.rb
1383 def need_associated_primary_key?
1384   true
1385 end

predicate_key()

The hash key to use for the eager loading predicate (left side of IN (1, 2, 3)). The left key qualified by the join table.

     # File lib/sequel/model/associations.rb
1350 def predicate_key
1351   cached_fetch(:predicate_key){qualify(join_table_alias, self[:left_key])}
1352 end

qualified_right_key()

The right key qualified by the join table.

     # File lib/sequel/model/associations.rb
1356 def qualified_right_key
1357   cached_fetch(:qualified_right_key){qualify(join_table_alias, self[:right_key])}
1358 end

qualified_right_primary_key()

right_primary_key qualified by the associated table

     # File lib/sequel/model/associations.rb
1388 def qualified_right_primary_key
1389   cached_fetch(:qualified_right_primary_key){qualify_assoc(right_primary_key)}
1390 end

right_primary_key()

The primary key column(s) to use in the associated table (can be symbol or array).

     # File lib/sequel/model/associations.rb
1393 def right_primary_key
1394   cached_fetch(:right_primary_key){associated_class.primary_key || raise(Error, "no primary key specified for #{associated_class.inspect}")}
1395 end

right_primary_key_method()

The method symbol or array of method symbols to call on the associated objects to get the foreign key values for the join table.

     # File lib/sequel/model/associations.rb
1404 def right_primary_key_method
1405   cached_fetch(:right_primary_key_method){right_primary_key}
1406 end

right_primary_key_methods()

The array of method symbols to call on the associated objects to get the foreign key values for the join table.

     # File lib/sequel/model/associations.rb
1410 def right_primary_key_methods
1411   cached_fetch(:right_primary_key_methods){Array(right_primary_key_method)}
1412 end

right_primary_keys()

The primary key columns to use in the associated table (always array).

     # File lib/sequel/model/associations.rb
1398 def right_primary_keys
1399   cached_fetch(:right_primary_keys){Array(right_primary_key)}
1400 end

select()

The columns to select when loading the association, associated_class.table_name.* by default.

     # File lib/sequel/model/associations.rb
1415 def select
1416   cached_fetch(:select){default_select}
1417 end

separate_query_per_table?()

Whether a separate query should be used for the join table.

     # File lib/sequel/model/associations.rb
1420 def separate_query_per_table?
1421   self[:join_table_db]
1422 end