From 524238139025ccddfa886bcfd7a1a6434954e305 Mon Sep 17 00:00:00 2001 From: Yasyf Mohamedali Date: Mon, 2 Mar 2015 17:18:35 -0500 Subject: Honour the order of the joining model in a `has_many :through` association when eager loading. Previously, eager loading a `has_many :through` association with no defined order would return the records in the natural order of the database. Now, these records will be returned in the order that the joining record is returned, in case there is a defined order there. --- .../associations/preloader/association.rb | 2 +- .../associations/preloader/through_association.rb | 23 ++++++++++++++-------- 2 files changed, 16 insertions(+), 9 deletions(-) (limited to 'activerecord/lib/active_record') diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb index 1dc8bff193..91de52e7e7 100644 --- a/activerecord/lib/active_record/associations/preloader/association.rb +++ b/activerecord/lib/active_record/associations/preloader/association.rb @@ -86,7 +86,7 @@ module ActiveRecord if owner_keys.any? # Some databases impose a limit on the number of ids in a list (in Oracle it's 1000) # Make several smaller queries if necessary or make one query if the adapter supports it - sliced = owner_keys.each_slice(klass.connection.in_clause_length || owner_keys.size) + sliced = owner_keys.each_slice(klass.connection.in_clause_length || owner_keys.size) records = load_slices sliced records.each do |record, owner_key| diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb index 56aa23b173..5adb0aac65 100644 --- a/activerecord/lib/active_record/associations/preloader/through_association.rb +++ b/activerecord/lib/active_record/associations/preloader/through_association.rb @@ -37,12 +37,7 @@ module ActiveRecord } end - record_offset = {} - @preloaded_records.each_with_index do |record,i| - record_offset[record] = i - end - - through_records.each_with_object({}) { |(lhs,center),records_by_owner| + through_records.each_with_object({}) do |(lhs,center), records_by_owner| pl_to_middle = center.group_by { |record| middle_to_pl[record] } records_by_owner[lhs] = pl_to_middle.flat_map do |pl, middles| @@ -52,13 +47,25 @@ module ActiveRecord association.reader }.compact - rhs_records.sort_by { |rhs| record_offset[rhs] } + # Respect the order on `reflection_scope` if it exists, else use the natural order. + if reflection_scope.values[:order].present? + @id_map ||= id_to_index_map @preloaded_records + rhs_records.sort_by { |rhs| @id_map[rhs] } + else + rhs_records + end end - } + end end private + def id_to_index_map(ids) + id_map = {} + ids.each_with_index { |id, index| id_map[id] = index } + id_map + end + def reset_association(owners, association_name) should_reset = (through_scope != through_reflection.klass.unscoped) || (reflection.options[:source_type] && through_reflection.collection?) -- cgit v1.2.3