Class: Sequel::Model::Associations::ManyToManyAssociationReflection

Class

Sequel::Model::Associations::ManyToManyAssociationReflection

In:

lib/sequel/model/associations.rb

Parent:

AssociationReflection

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

Public Instance methods

associated_key_alias()

The alias to use for the associated key when eagerly loading

      # File lib/sequel/model/associations.rb, line 1183
1183:         def associated_key_alias
1184:           self[:left_key_alias]
1185:         end

associated_key_array()

Array of associated keys used when eagerly loading.

      # File lib/sequel/model/associations.rb, line 1188
1188:         def associated_key_array
1189:           cached_fetch(:associated_key_array) do
1190:             if self[:uses_left_composite_keys]
1191:               associated_key_alias.zip(predicate_keys).map{|a, k| SQL::AliasedExpression.new(k, a)}
1192:             else
1193:               [SQL::AliasedExpression.new(predicate_key, associated_key_alias)]
1194:             end
1195:           end
1196:         end

associated_key_column()

The column to use for the associated key when eagerly loading

      # File lib/sequel/model/associations.rb, line 1199
1199:         def associated_key_column
1200:           self[:left_key]
1201:         end

associated_key_table()

Alias for join_table_alias

associated_object_keys()

Alias of right_primary_keys

      # File lib/sequel/model/associations.rb, line 1204
1204:         def associated_object_keys
1205:           right_primary_keys
1206:         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, line 1210
1210:         def can_have_associated_objects?(obj)
1211:           !self[:left_primary_keys].any?{|k| obj.get_column_value(k).nil?}
1212:         end

cloneable?(ref)

one_through_one and many_to_many associations can be clones

      # File lib/sequel/model/associations.rb, line 1215
1215:         def cloneable?(ref)
1216:           ref[:type] == :many_to_many || ref[:type] == :one_through_one
1217:         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, line 1221
1221:         def default_associated_key_alias
1222:           self[:uses_left_composite_keys] ? (0...self[:left_keys].length).map{|i| "x_foreign_key_#{i}_x""x_foreign_key_#{i}_x"} : :x_foreign_key_x
1223:         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, line 1227
1227:         def default_eager_loader(eo)
1228:           h = eo[:id_map]
1229:           assign_singular = assign_singular?
1230:           delete_rn = delete_row_number_column
1231:           uses_lcks = self[:uses_left_composite_keys]
1232:           left_key_alias = self[:left_key_alias]
1233:           name = self[:name]
1234: 
1235:           self[:model].eager_load_results(self, eo) do |assoc_record|
1236:             assoc_record.values.delete(delete_rn) if delete_rn
1237:             hash_key = if uses_lcks
1238:               left_key_alias.map{|k| assoc_record.values.delete(k)}
1239:             else
1240:               assoc_record.values.delete(left_key_alias)
1241:             end
1242:             next unless objects = h[hash_key]
1243:             if assign_singular
1244:               objects.each do |object| 
1245:                 object.associations[name] ||= assoc_record
1246:               end
1247:             else
1248:               objects.each do |object|
1249:                 object.associations[name].push(assoc_record)
1250:               end
1251:             end
1252:           end
1253:         end

default_join_table()

Default name symbol for the join table.

      # File lib/sequel/model/associations.rb, line 1256
1256:         def default_join_table
1257:           [self[:class_name], self[:model].name].map{|i| underscore(pluralize(demodulize(i)))}.sort.join('_').to_sym
1258:         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, line 1262
1262:         def default_left_key
1263: 
1264:           "#{underscore(demodulize(self[:model].name))}_id"
1265:         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, line 1268
1268:         def default_right_key
1269: 
1270:           "#{singularize(self[:name])}_id"
1271:         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, line 1301
1301:         def eager_loading_use_associated_key?
1302:           true
1303:         end

finalize_settings()

      # File lib/sequel/model/associations.rb, line 1284
1284:         def finalize_settings
1285:           FINALIZE_SETTINGS
1286:         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, line 1313
1313:         def join_table_alias
1314:           cached_fetch(:join_table_alias) do
1315:             s, a = split_join_table_alias
1316:             a || s
1317:           end
1318:         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, line 1307
1307:         def join_table_source
1308:           cached_fetch(:join_table_source){split_join_table_alias[0]}
1309:         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, line 1323
1323:         def need_associated_primary_key?
1324:           true
1325:         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, line 1290
1290:         def predicate_key
1291:           cached_fetch(:predicate_key){qualify(join_table_alias, self[:left_key])}
1292:         end

qualified_left_key()

Alias for predicate_key

qualified_right_key()

The right key qualified by the join table.

      # File lib/sequel/model/associations.rb, line 1296
1296:         def qualified_right_key
1297:           cached_fetch(:qualified_right_key){qualify(join_table_alias, self[:right_key])}
1298:         end

qualified_right_primary_key()

right_primary_key qualified by the associated table

      # File lib/sequel/model/associations.rb, line 1328
1328:         def qualified_right_primary_key
1329:           cached_fetch(:qualified_right_primary_key){qualify_assoc(right_primary_key)}
1330:         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, line 1333
1333:         def right_primary_key
1334:           cached_fetch(:right_primary_key){associated_class.primary_key || raise(Error, "no primary key specified for #{associated_class.inspect}")}
1335:         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, line 1344
1344:         def right_primary_key_method
1345:           cached_fetch(:right_primary_key_method){right_primary_key}
1346:         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, line 1350
1350:         def right_primary_key_methods
1351:           cached_fetch(:right_primary_key_methods){Array(right_primary_key_method)}
1352:         end

right_primary_keys()

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

      # File lib/sequel/model/associations.rb, line 1338
1338:         def right_primary_keys
1339:           cached_fetch(:right_primary_keys){Array(right_primary_key)}
1340:         end

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

      # File lib/sequel/model/associations.rb, line 1355
1355:         def select
1356:           cached_fetch(:select){default_select}
1357:         end