module ActiveRecord # = Active Record Has Many Association module Associations # This is the proxy that handles a has many association. # # If the association has a :through option further specialization # is provided by its child HasManyThroughAssociation. class HasManyAssociation < AssociationCollection #:nodoc: def initialize(owner, reflection) @finder_sql = nil super end protected def owner_quoted_id if @reflection.options[:primary_key] quote_value(@owner.send(@reflection.options[:primary_key])) else @owner.quoted_id end end # Returns the number of records in this collection. # # If the association has a counter cache it gets that value. Otherwise # it will attempt to do a count via SQL, bounded to :limit if # there's one. Some configuration options like :group make it impossible # to do a SQL count, in those cases the array count will be used. # # That does not depend on whether the collection has already been loaded # or not. The +size+ method is the one that takes the loaded flag into # account and delegates to +count_records+ if needed. # # If the collection is empty the target is set to an empty array and # the loaded flag is set to true as well. def count_records count = if has_cached_counter? @owner.send(:read_attribute, cached_counter_attribute_name) elsif @reflection.options[:counter_sql] @reflection.klass.count_by_sql(@counter_sql) else @reflection.klass.count(:conditions => @counter_sql, :include => @reflection.options[:include]) end # If there's nothing in the database and @target has no new records # we are certain the current target is an empty array. This is a # documented side-effect of the method that may avoid an extra SELECT. @target ||= [] and loaded if count == 0 if @reflection.options[:limit] count = [ @reflection.options[:limit], count ].min end return count end def has_cached_counter? @owner.attribute_present?(cached_counter_attribute_name) end def cached_counter_attribute_name "#{@reflection.name}_count" end def insert_record(record, force = false, validate = true) set_belongs_to_association_for(record) force ? record.save! : record.save(:validate => validate) end # Deletes the records according to the :dependent option. def delete_records(records) case @reflection.options[:dependent] when :destroy records.each { |r| r.destroy } when :delete_all @reflection.klass.delete(records.map { |record| record.id }) else relation = Arel::Table.new(@reflection.table_name) relation.where(relation[@reflection.primary_key_name].eq(@owner.id). and(Arel::Predicates::In.new(relation[@reflection.klass.primary_key], records.map(&:id))) ).update(relation[@reflection.primary_key_name] => nil) @owner.class.update_counters(@owner.id, cached_counter_attribute_name => -records.size) if has_cached_counter? end end def target_obsolete? false end def construct_sql case when @reflection.options[:finder_sql] @finder_sql = interpolate_sql(@reflection.options[:finder_sql]) when @reflection.options[:as] @finder_sql = "#{@reflection.quoted_table_name}.#{@reflection.options[:as]}_id = #{owner_quoted_id} AND " + "#{@reflection.quoted_table_name}.#{@reflection.options[:as]}_type = #{@owner.class.quote_value(@owner.class.base_class.name.to_s)}" @finder_sql << " AND (#{conditions})" if conditions else @finder_sql = "#{@reflection.quoted_table_name}.#{@reflection.primary_key_name} = #{owner_quoted_id}" @finder_sql << " AND (#{conditions})" if conditions end construct_counter_sql end def construct_scope create_scoping = {} set_belongs_to_association_for(create_scoping) { :find => { :conditions => @finder_sql, :readonly => false, :order => @reflection.options[:order], :limit => @reflection.options[:limit], :include => @reflection.options[:include]}, :create => create_scoping } end def we_can_set_the_inverse_on_this?(record) inverse = @reflection.inverse_of return !inverse.nil? end end end end