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

Inherits:
AssociationReflection show all
Defined in:
lib/sequel/model/associations.rb

Constant Summary

Constants included from Inflections

Inflections::CAMELIZE_CONVERT_REGEXP, Inflections::CAMELIZE_MODULE_REGEXP, Inflections::DASH, Inflections::DEMODULIZE_CONVERT_REGEXP, Inflections::EMPTY_STRING, Inflections::SLASH, Inflections::UNDERSCORE, Inflections::UNDERSCORE_CONVERT_REGEXP1, Inflections::UNDERSCORE_CONVERT_REGEXP2, Inflections::UNDERSCORE_CONVERT_REPLACE, Inflections::UNDERSCORE_MODULE_REGEXP, Inflections::VALID_CONSTANT_NAME_REGEXP

Instance Method Summary collapse

Methods inherited from AssociationReflection

#_add_method, #_dataset_method, #_remove_all_method, #_remove_method, #_setter_method, #add_method, #associated_class, #association_method, #dataset_method, #dataset_need_primary_key?, #eager_graph_lazy_dataset?, #eager_limit_strategy, #eager_loader_key, #eager_loading_predicate_key, #limit_and_offset, #predicate_keys, #qualify, #qualify_assoc, #qualify_cur, #reciprocal_array?, #remove_all_method, #remove_before_destroy?, #remove_method, #remove_should_check_existing?, #returns_array?, #set_reciprocal_to_self?, #setter_method

Methods included from Inflections

clear, irregular, plural, singular, uncountable

Methods inherited from Hash

#&, #case, #hstore, #pg_json, #sql_expr, #sql_negate, #sql_or, #|, #~

Instance Method Details

#associated_key_alias ⇒ Object

The alias to use for the associated key when eagerly loading



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# File 'lib/sequel/model/associations.rb', line 471

def associated_key_alias
  self[:left_key_alias]
end

#associated_key_column ⇒ Object

The column to use for the associated key when eagerly loading



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# File 'lib/sequel/model/associations.rb', line 476

def associated_key_column
  self[:left_key]
end

#associated_object_keys ⇒ Object

Alias of right_primary_keys



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# File 'lib/sequel/model/associations.rb', line 481

def associated_object_keys
  right_primary_keys
end

#can_have_associated_objects?(obj) ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/sequel/model/associations.rb', line 487

def can_have_associated_objects?(obj)
  !self[:left_primary_keys].any?{|k| obj.send(k).nil?}
end

#default_associated_key_alias ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 493

def default_associated_key_alias
  self[:uses_left_composite_keys] ? (0...self[:left_keys].length).map{|i| :"x_foreign_key_#{i}_x"} : :x_foreign_key_x
end

#default_join_table ⇒ Object

Default name symbol for the join table.



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# File 'lib/sequel/model/associations.rb', line 498

def default_join_table
  [self[:class_name], self[:model].name].map{|i| underscore(pluralize(demodulize(i)))}.sort.join('_').to_sym
end

#default_left_key ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 504

def default_left_key
  :"#{underscore(demodulize(self[:model].name))}_id"
end

#default_right_key ⇒ Object

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).



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# File 'lib/sequel/model/associations.rb', line 510

def default_right_key
  :"#{singularize(self[:name])}_id"
end

#eager_loading_use_associated_key? ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/sequel/model/associations.rb', line 527

def eager_loading_use_associated_key?
  true
end

#join_table_alias ⇒ Object Also known as: associated_key_table

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



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# File 'lib/sequel/model/associations.rb', line 539

def join_table_alias
  cached_fetch(:join_table_alias) do
    s, a = split_join_table_alias
    a || s
  end
end

#join_table_source ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 533

def join_table_source
  cached_fetch(:join_table_source){split_join_table_alias[0]}
end

#need_associated_primary_key? ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/sequel/model/associations.rb', line 549

def need_associated_primary_key?
  true
end

#predicate_key ⇒ Object Also known as: qualified_left_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.



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# File 'lib/sequel/model/associations.rb', line 516

def predicate_key
  cached_fetch(:predicate_key){qualify(join_table_alias, self[:left_key])}
end

#qualified_right_key ⇒ Object

The right key qualified by the join table.



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# File 'lib/sequel/model/associations.rb', line 522

def qualified_right_key
  cached_fetch(:qualified_right_key){qualify(join_table_alias, self[:right_key])}
end

#qualified_right_primary_key ⇒ Object

#right_primary_key qualified by the associated table



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# File 'lib/sequel/model/associations.rb', line 573

def qualified_right_primary_key
  cached_fetch(:qualified_right_primary_key){qualify_assoc(right_primary_key)}
end

#reciprocal ⇒ Object

Returns the reciprocal association symbol, if one exists.



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# File 'lib/sequel/model/associations.rb', line 554

def reciprocal
  cached_fetch(:reciprocal) do
    left_keys = self[:left_keys]
    right_keys = self[:right_keys]
    join_table = self[:join_table]
    recip = nil
    associated_class.all_association_reflections.each do |assoc_reflect|
      if assoc_reflect[:type] == :many_to_many && assoc_reflect[:left_keys] == right_keys &&
         assoc_reflect[:right_keys] == left_keys && assoc_reflect[:join_table] == join_table &&
         assoc_reflect.associated_class == self[:model]
        recip = assoc_reflect[:name]
        break
      end
    end
    recip
  end
end

#right_primary_key ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 578

def right_primary_key
  cached_fetch(:right_primary_key){associated_class.primary_key}
end

#right_primary_key_method ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 589

def right_primary_key_method
  cached_fetch(:right_primary_key_method){right_primary_key}
end

#right_primary_key_methods ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 595

def right_primary_key_methods
  cached_fetch(:right_primary_key_methods){Array(right_primary_key_method)}
end

#right_primary_keys ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 583

def right_primary_keys
  cached_fetch(:right_primary_keys){Array(right_primary_key)}
end

#select ⇒ Object

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



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# File 'lib/sequel/model/associations.rb', line 600

def select
 cached_fetch(:select){Sequel::SQL::ColumnAll.new(associated_class.table_name)}
end