diff options
Diffstat (limited to 'activerecord/lib/active_record')
| -rw-r--r-- | activerecord/lib/active_record/associations.rb | 410 | ||||
| -rw-r--r-- | activerecord/lib/active_record/relation/query_methods.rb | 13 |
2 files changed, 266 insertions, 157 deletions
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb index 565ebf8197..bf13898e92 100644 --- a/activerecord/lib/active_record/associations.rb +++ b/activerecord/lib/active_record/associations.rb @@ -1924,7 +1924,9 @@ module ActiveRecord reflection = parent.reflections[associations.to_s.intern] or raise ConfigurationError, "Association named '#{ associations }' was not found; perhaps you misspelled it?" @reflections << reflection - @joins << build_join_association(reflection, parent).with_join_class(join_class) + join_association = build_join_association(reflection, parent) + join_association.join_class = join_class + @joins << join_association when Array associations.each do |association| build(association, parent, join_class) @@ -2005,35 +2007,51 @@ module ActiveRecord association_proxy = record.send("set_#{join.reflection.name}_target", association) association_proxy.__send__(:set_inverse_instance, association, record) end - - class JoinBase # :nodoc: - attr_reader :active_record, :table_joins - delegate :table_name, :column_names, :primary_key, :reflections, :sanitize_sql, :arel_engine, :to => :active_record - - def initialize(active_record, joins = nil) + + # A JoinPart represents a part of a JoinDependency. It is an abstract class, inherited + # by JoinBase and JoinAssociation. A JoinBase represents the Active Record which + # everything else is being joined onto. A JoinAssociation represents an association which + # is joining to the base. A JoinAssociation may result in more than one actual join + # operations (for example a has_and_belongs_to_many JoinAssociation would result in + # two; one for the join table and one for the target table). + class JoinPart # :nodoc: + # The Active Record class which this join part is associated 'about'; for a JoinBase + # this is the actual base model, for a JoinAssociation this is the target model of the + # association. + attr_reader :active_record + + delegate :table_name, :column_names, :primary_key, :reflections, :sanitize_sql, :arel_engine, :to => :active_record + + def initialize(active_record) @active_record = active_record @cached_record = {} - @table_joins = joins end - + def ==(other) - other.class == self.class && - other.active_record == active_record && - other.table_joins == table_joins + raise NotImplementedError end - + + # An Arel::Table for the active_record + def table + raise NotImplementedError + end + + # The prefix to be used when aliasing columns in the active_record's table def aliased_prefix - "t0" + raise NotImplementedError end - + + # The alias for the active_record's table + def aliased_table_name + raise NotImplementedError + end + + # The alias for the primary key of the active_record's table def aliased_primary_key "#{aliased_prefix}_r0" end - - def aliased_table_name - active_record.table_name - end - + + # An array of [column_name, alias] pairs for the table def column_names_with_alias unless defined?(@column_names_with_alias) @column_names_with_alias = [] @@ -2059,33 +2077,74 @@ module ActiveRecord end end - class JoinAssociation < JoinBase # :nodoc: - attr_reader :reflection, :parent, :aliased_table_name, :aliased_prefix, :aliased_join_table_name, :parent_table_name, :join_class - delegate :options, :klass, :through_reflection, :source_reflection, :to => :reflection + class JoinBase < JoinPart # :nodoc: + # Extra joins provided when the JoinDependency was created + attr_reader :table_joins + + def initialize(active_record, joins = nil) + super(active_record) + @table_joins = joins + end + + def ==(other) + other.class == self.class && + other.active_record == active_record && + other.table_joins == table_joins + end + + def aliased_prefix + "t0" + end + + def table + Arel::Table.new(table_name, :engine => arel_engine, :columns => active_record.columns) + end + + def aliased_table_name + active_record.table_name + end + end + + class JoinAssociation < JoinPart # :nodoc: + # The reflection of the association represented + attr_reader :reflection + + # The JoinDependency object which this JoinAssociation exists within. This is mainly + # relevant for generating aliases which do not conflict with other joins which are + # part of the query. + attr_reader :join_dependency + + # A JoinBase instance representing the active record we are joining onto. + # (So in Author.has_many :posts, the Author would be that base record.) + attr_reader :parent + + # What type of join will be generated, either Arel::InnerJoin (default) or Arel::OuterJoin + attr_accessor :join_class + + # These implement abstract methods from the superclass + attr_reader :aliased_prefix, :aliased_table_name + + delegate :options, :through_reflection, :source_reflection, :to => :reflection + delegate :table, :table_name, :to => :parent, :prefix => true def initialize(reflection, join_dependency, parent = nil) reflection.check_validity! + if reflection.options[:polymorphic] raise EagerLoadPolymorphicError.new(reflection) end super(reflection.klass) - @join_dependency = join_dependency - @parent = parent - @reflection = reflection - @aliased_prefix = "t#{ join_dependency.joins.size }" - @parent_table_name = parent.active_record.table_name - @aliased_table_name = aliased_table_name_for(table_name) - @join = nil - @join_class = Arel::InnerJoin - - if reflection.macro == :has_and_belongs_to_many - @aliased_join_table_name = aliased_table_name_for(reflection.options[:join_table], "_join") - end - - if [:has_many, :has_one].include?(reflection.macro) && reflection.options[:through] - @aliased_join_table_name = aliased_table_name_for(reflection.through_reflection.klass.table_name, "_join") - end + + @reflection = reflection + @join_dependency = join_dependency + @parent = parent + @join_class = Arel::InnerJoin + + # This must be done eagerly upon initialisation because the alias which is produced + # depends on the state of the join dependency, but we want it to work the same way + # every time. + allocate_aliases end def ==(other) @@ -2099,59 +2158,25 @@ module ActiveRecord self.parent == join end end - - def with_join_class(join_class) - @join_class = join_class - self + + def join_to(relation) + send("join_#{reflection.macro}_to", relation) end - def association_join - return @join if @join - - aliased_table = Arel::Table.new(table_name, :as => @aliased_table_name, - :engine => arel_engine, - :columns => klass.columns) - - parent_table = Arel::Table.new(parent.table_name, :as => parent.aliased_table_name, - :engine => arel_engine, - :columns => parent.active_record.columns) - - @join = send("build_#{reflection.macro}", aliased_table, parent_table) - - unless klass.descends_from_active_record? - sti_column = aliased_table[klass.inheritance_column] - sti_condition = sti_column.eq(klass.sti_name) - klass.descendants.each {|subclass| sti_condition = sti_condition.or(sti_column.eq(subclass.sti_name)) } - - @join << sti_condition - end - - [through_reflection, reflection].each do |ref| - if ref && ref.options[:conditions] - @join << interpolate_sql(sanitize_sql(ref.options[:conditions], aliased_table_name)) - end - end - - @join + def join_relation(joining_relation) + self.join_class = Arel::OuterJoin + joining_relation.joins(self) end - - def relation - aliased = Arel::Table.new(table_name, :as => @aliased_table_name, - :engine => arel_engine, - :columns => klass.columns) - - if reflection.macro == :has_and_belongs_to_many - [Arel::Table.new(options[:join_table], :as => aliased_join_table_name, :engine => arel_engine), aliased] - elsif reflection.options[:through] - [Arel::Table.new(through_reflection.klass.table_name, :as => aliased_join_table_name, :engine => arel_engine), aliased] - else - aliased - end - end - - def join_relation(joining_relation, join = nil) - joining_relation.joins(self.with_join_class(Arel::OuterJoin)) + + def table + @table ||= Arel::Table.new( + table_name, :as => aliased_table_name, + :engine => arel_engine, :columns => active_record.columns + ) end + + # More semantic name given we are talking about associations + alias_method :target_table, :table protected @@ -2193,74 +2218,169 @@ module ActiveRecord end private + + def allocate_aliases + @aliased_prefix = "t#{ join_dependency.joins.size }" + @aliased_table_name = aliased_table_name_for(table_name) + + if reflection.macro == :has_and_belongs_to_many + @aliased_join_table_name = aliased_table_name_for(reflection.options[:join_table], "_join") + elsif [:has_many, :has_one].include?(reflection.macro) && reflection.options[:through] + @aliased_join_table_name = aliased_table_name_for(reflection.through_reflection.klass.table_name, "_join") + end + end + + def process_conditions(conditions, table_name) + Arel.sql(interpolate_sql(sanitize_sql(conditions, table_name))) + end + + def join_target_table(relation, *conditions) + relation = relation.join(target_table, join_class) + + # If the target table is an STI model then we must be sure to only include records of + # its type and its sub-types. + unless active_record.descends_from_active_record? + sti_column = target_table[active_record.inheritance_column] + + sti_condition = sti_column.eq(active_record.sti_name) + active_record.descendants.each do |subclass| + sti_condition = sti_condition.or(sti_column.eq(subclass.sti_name)) + end + + conditions << sti_condition + end + + # If the reflection has conditions, add them + if options[:conditions] + conditions << process_conditions(options[:conditions], aliased_table_name) + end + + relation = relation.on(*conditions) + end - def build_has_and_belongs_to_many(aliased_table, parent_table) - join_table = Arel::Table.new(options[:join_table], :as => aliased_join_table_name, :engine => arel_engine) - fk = options[:foreign_key] || reflection.active_record.to_s.foreign_key - klass_fk = options[:association_foreign_key] || klass.to_s.foreign_key - - [ - join_table[fk].eq(parent_table[reflection.active_record.primary_key]), - aliased_table[klass.primary_key].eq(join_table[klass_fk]) - ] + def join_has_and_belongs_to_many_to(relation) + join_table = Arel::Table.new( + options[:join_table], :engine => arel_engine, + :as => @aliased_join_table_name + ) + + fk = options[:foreign_key] || reflection.active_record.to_s.foreign_key + klass_fk = options[:association_foreign_key] || reflection.klass.to_s.foreign_key + + relation = relation.join(join_table, join_class) + relation = relation.on( + join_table[fk]. + eq(parent_table[reflection.active_record.primary_key]) + ) + + join_target_table( + relation, + target_table[reflection.klass.primary_key]. + eq(join_table[klass_fk]) + ) end - def build_has_many(aliased_table, parent_table) + def join_has_many_to(relation) if reflection.options[:through] - join_table = Arel::Table.new(through_reflection.klass.table_name, - :as => aliased_join_table_name, - :engine => arel_engine) - jt_foreign_key = jt_as_extra = jt_source_extra = jt_sti_extra = nil - first_key = second_key = nil - - if through_reflection.options[:as] # has_many :through against a polymorphic join - as_key = through_reflection.options[:as].to_s - jt_foreign_key = as_key + '_id' - jt_as_extra = join_table[as_key + '_type'].eq(parent.active_record.base_class.name) - else - jt_foreign_key = through_reflection.primary_key_name - end - - case source_reflection.macro - when :has_many - second_key = options[:foreign_key] || primary_key + join_has_many_through_to(relation) + elsif reflection.options[:as] + join_has_many_polymorphic_to(relation) + else + foreign_key = options[:foreign_key] || reflection.active_record.name.foreign_key + primary_key = options[:primary_key] || parent.primary_key + + join_target_table( + relation, + target_table[foreign_key]. + eq(parent_table[primary_key]) + ) + end + end + alias :join_has_one_to :join_has_many_to + + def join_has_many_through_to(relation) + join_table = Arel::Table.new( + through_reflection.klass.table_name, :engine => arel_engine, + :as => @aliased_join_table_name + ) + + jt_conditions = [] + jt_foreign_key = first_key = second_key = nil + + if through_reflection.options[:as] # has_many :through against a polymorphic join + as_key = through_reflection.options[:as].to_s + jt_foreign_key = as_key + '_id' + + jt_conditions << + join_table[as_key + '_type']. + eq(parent.active_record.base_class.name) + else + jt_foreign_key = through_reflection.primary_key_name + end - if source_reflection.options[:as] - first_key = "#{source_reflection.options[:as]}_id" - else - first_key = through_reflection.klass.base_class.to_s.foreign_key - end + case source_reflection.macro + when :has_many + second_key = options[:foreign_key] || primary_key - unless through_reflection.klass.descends_from_active_record? - jt_sti_extra = join_table[through_reflection.active_record.inheritance_column].eq(through_reflection.klass.sti_name) - end - when :belongs_to - first_key = primary_key - if reflection.options[:source_type] - second_key = source_reflection.association_foreign_key - jt_source_extra = join_table[reflection.source_reflection.options[:foreign_type]].eq(reflection.options[:source_type]) - else - second_key = source_reflection.primary_key_name - end + if source_reflection.options[:as] + first_key = "#{source_reflection.options[:as]}_id" + else + first_key = through_reflection.klass.base_class.to_s.foreign_key end - [ - [parent_table[parent.primary_key].eq(join_table[jt_foreign_key]), jt_as_extra, jt_source_extra, jt_sti_extra].compact, - aliased_table[first_key].eq(join_table[second_key]) - ] - elsif reflection.options[:as] - id_rel = aliased_table["#{reflection.options[:as]}_id"].eq(parent_table[parent.primary_key]) - type_rel = aliased_table["#{reflection.options[:as]}_type"].eq(parent.active_record.base_class.name) - [id_rel, type_rel] - else - foreign_key = options[:foreign_key] || reflection.active_record.name.foreign_key - [aliased_table[foreign_key].eq(parent_table[reflection.options[:primary_key] || parent.primary_key])] + unless through_reflection.klass.descends_from_active_record? + jt_conditions << + join_table[through_reflection.active_record.inheritance_column]. + eq(through_reflection.klass.sti_name) + end + when :belongs_to + first_key = primary_key + + if reflection.options[:source_type] + second_key = source_reflection.association_foreign_key + + jt_conditions << + join_table[reflection.source_reflection.options[:foreign_type]]. + eq(reflection.options[:source_type]) + else + second_key = source_reflection.primary_key_name + end + end + + jt_conditions << + parent_table[parent.primary_key]. + eq(join_table[jt_foreign_key]) + + if through_reflection.options[:conditions] + jt_conditions << process_conditions(through_reflection.options[:conditions], aliased_table_name) end + + relation = relation.join(join_table, join_class).on(*jt_conditions) + + join_target_table( + relation, + target_table[first_key].eq(join_table[second_key]) + ) + end + + def join_has_many_polymorphic_to(relation) + join_target_table( + relation, + target_table["#{reflection.options[:as]}_id"]. + eq(parent_table[parent.primary_key]), + target_table["#{reflection.options[:as]}_type"]. + eq(parent.active_record.base_class.name) + ) end - alias :build_has_one :build_has_many - def build_belongs_to(aliased_table, parent_table) - [aliased_table[options[:primary_key] || reflection.klass.primary_key].eq(parent_table[options[:foreign_key] || reflection.primary_key_name])] + def join_belongs_to_to(relation) + foreign_key = options[:foreign_key] || reflection.primary_key_name + primary_key = options[:primary_key] || reflection.klass.primary_key + + join_target_table( + relation, + target_table[primary_key].eq(parent_table[foreign_key]) + ) end end end diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index a5dc051c6e..59ce76ea42 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -221,19 +221,8 @@ module ActiveRecord @implicit_readonly = true unless association_joins.empty? && stashed_association_joins.empty? - to_join = [] - join_dependency.join_associations.each do |association| - if (association_relation = association.relation).is_a?(Array) - to_join << [association_relation.first, association.join_class, association.association_join.first] - to_join << [association_relation.last, association.join_class, association.association_join.last] - else - to_join << [association_relation, association.join_class, association.association_join] - end - end - - to_join.uniq.each do |left, join_class, right| - relation = relation.join(left, join_class).on(*right) + relation = association.join_to(relation) end relation.join(custom_joins) |