diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/preloader/association.rb')
-rw-r--r-- | activerecord/lib/active_record/associations/preloader/association.rb | 99 |
1 files changed, 70 insertions, 29 deletions
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb index cbf5e734ea..a6e1a24360 100644 --- a/activerecord/lib/active_record/associations/preloader/association.rb +++ b/activerecord/lib/active_record/associations/preloader/association.rb @@ -3,6 +3,7 @@ module ActiveRecord class Preloader class Association #:nodoc: attr_reader :owners, :reflection, :preload_scope, :model, :klass + attr_reader :preloaded_records def initialize(klass, owners, reflection, preload_scope) @klass = klass @@ -12,15 +13,14 @@ module ActiveRecord @model = owners.first && owners.first.class @scope = nil @owners_by_key = nil + @preloaded_records = [] end - def run - unless owners.first.association(reflection.name).loaded? - preload - end + def run(preloader) + preload(preloader) end - def preload + def preload(preloader) raise NotImplementedError end @@ -29,7 +29,11 @@ module ActiveRecord end def records_for(ids) - scope.where(association_key.in(ids)) + query_scope(ids) + end + + def query_scope(ids) + scope.where(association_key_name => ids) end def table @@ -52,13 +56,16 @@ module ActiveRecord raise NotImplementedError end - # We're converting to a string here because postgres will return the aliased association - # key in a habtm as a string (for whatever reason) def owners_by_key - @owners_by_key ||= owners.group_by do |owner| - key = owner[owner_key_name] - key && key.to_s - end + @owners_by_key ||= if key_conversion_required? + owners.group_by do |owner| + owner[owner_key_name].to_s + end + else + owners.group_by do |owner| + owner[owner_key_name] + end + end end def options @@ -67,53 +74,87 @@ module ActiveRecord private - def associated_records_by_owner + def associated_records_by_owner(preloader) owners_map = owners_by_key owner_keys = owners_map.keys.compact - if klass.nil? || owner_keys.empty? - records = [] - else - # 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(model.connection.in_clause_length || owner_keys.size) - records = sliced.map { |slice| records_for(slice).to_a }.flatten + # Each record may have multiple owners, and vice-versa + records_by_owner = owners.each_with_object({}) do |owner,h| + h[owner] = [] end - # Each record may have multiple owners, and vice-versa - records_by_owner = Hash[owners.map { |owner| [owner, []] }] - records.each do |record| - owner_key = record[association_key_name].to_s + 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) - owners_map[owner_key].each do |owner| - records_by_owner[owner] << record + records = load_slices sliced + records.each do |record, owner_key| + owners_map[owner_key].each do |owner| + records_by_owner[owner] << record + end end end + records_by_owner end + def key_conversion_required? + association_key_type != owner_key_type + end + + def association_key_type + @klass.type_for_attribute(association_key_name.to_s).type + end + + def owner_key_type + @model.type_for_attribute(owner_key_name.to_s).type + end + + def load_slices(slices) + @preloaded_records = slices.flat_map { |slice| + records_for(slice) + } + + @preloaded_records.map { |record| + key = record[association_key_name] + key = key.to_s if key_conversion_required? + + [record, key] + } + end + def reflection_scope @reflection_scope ||= reflection.scope ? klass.unscoped.instance_exec(nil, &reflection.scope) : klass.unscoped end def build_scope scope = klass.unscoped - scope.default_scoped = true values = reflection_scope.values + reflection_binds = reflection_scope.bind_values preload_values = preload_scope.values + preload_binds = preload_scope.bind_values scope.where_values = Array(values[:where]) + Array(preload_values[:where]) scope.references_values = Array(values[:references]) + Array(preload_values[:references]) + scope.bind_values = (reflection_binds + preload_binds) - scope.select! preload_values[:select] || values[:select] || table[Arel.star] + scope._select! preload_values[:select] || values[:select] || table[Arel.star] scope.includes! preload_values[:includes] || values[:includes] + scope.joins! preload_values[:joins] || values[:joins] + scope.order! preload_values[:order] || values[:order] + + if preload_values[:readonly] || values[:readonly] + scope.readonly! + end if options[:as] scope.where!(klass.table_name => { reflection.type => model.base_class.sti_name }) end - scope + scope.unscope_values = Array(values[:unscope]) + klass.default_scoped.merge(scope) end end end |