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Delay building arel relation as long as possible for improved introsp…

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1 parent b078f7f commit a04486dc997979a2d87fc013d30b6e71a3df4a64 @lifo lifo committed Jan 12, 2010
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15 activerecord/lib/active_record/associations.rb
@@ -2148,22 +2148,23 @@ def association_join
end
def relation
+ aliased = Arel::Table.new(table_name, :as => @aliased_table_name)
+
if reflection.macro == :has_and_belongs_to_many
- [Arel::Table.new(table_alias_for(options[:join_table], aliased_join_table_name)), Arel::Table.new(table_name_and_alias)]
+ [Arel::Table.new(options[:join_table], :as => aliased_join_table_name), aliased]
elsif reflection.options[:through]
- [Arel::Table.new(table_alias_for(through_reflection.klass.table_name, aliased_join_table_name)), Arel::Table.new(table_name_and_alias)]
+ [Arel::Table.new(through_reflection.klass.table_name, :as => aliased_join_table_name), aliased]
else
- Arel::Table.new(table_name_and_alias)
+ aliased
end
end
def join_relation(joining_relation, join = nil)
if (relations = relation).is_a?(Array)
- joining_relation.
- joins(relations.first, Arel::OuterJoin).on(association_join.first).
- joins(relations.last, Arel::OuterJoin).on(association_join.last)
+ joining_relation.joins(Relation::JoinOperation.new(relations.first, Arel::OuterJoin, association_join.first)).
+ joins(Relation::JoinOperation.new(relations.last, Arel::OuterJoin, association_join.last))
else
- joining_relation.joins(relations, Arel::OuterJoin).on(association_join)
+ joining_relation.joins(Relation::JoinOperation.new(relations, Arel::OuterJoin, association_join))
end
end
View
4 activerecord/lib/active_record/base.rb
@@ -1663,7 +1663,7 @@ def merge_joins(*joins)
def build_association_joins(joins)
join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(self, joins, nil)
- relation = active_relation.relation
+ relation = active_relation.table
join_dependency.join_associations.map { |association|
if (association_relation = association.relation).is_a?(Array)
[Arel::InnerJoin.new(relation, association_relation.first, association.association_join.first).joins(relation),
@@ -2039,7 +2039,7 @@ def expand_hash_conditions_for_aggregates(attrs)
def sanitize_sql_hash_for_conditions(attrs, default_table_name = self.table_name)
attrs = expand_hash_conditions_for_aggregates(attrs)
- table = Arel::Table.new(default_table_name, active_relation_engine)
+ table = Arel::Table.new(self.table_name, :engine => active_relation_engine, :as => default_table_name)
builder = PredicateBuilder.new(active_relation_engine)
builder.build_from_hash(attrs, table).map(&:to_sql).join(' AND ')
end
View
72 activerecord/lib/active_record/relation.rb
@@ -1,19 +1,19 @@
module ActiveRecord
class Relation
- include QueryMethods, FinderMethods, CalculationMethods, SpawnMethods
+ JoinOperation = Struct.new(:relation, :join_class, :on)
+ ASSOCIATION_METHODS = [:includes, :eager_load, :preload]
+ MULTI_VALUE_METHODS = [:select, :group, :order, :joins, :where, :having]
+ SINGLE_VALUE_METHODS = [:limit, :offset, :lock, :readonly, :create_with, :from]
+
+ include FinderMethods, CalculationMethods, SpawnMethods, QueryMethods
delegate :length, :collect, :map, :each, :all?, :to => :to_a
- attr_reader :relation, :klass
- attr_writer :readonly, :table
- attr_accessor :preload_associations, :eager_load_associations, :includes_associations, :create_with_attributes
+ attr_reader :table, :klass
- def initialize(klass, relation)
- @klass, @relation = klass, relation
- @preload_associations = []
- @eager_load_associations = []
- @includes_associations = []
- @loaded, @readonly = false
+ def initialize(klass, table)
+ @klass, @table = klass, table
+ (ASSOCIATION_METHODS + MULTI_VALUE_METHODS).each {|v| instance_variable_set(:"@#{v}_values", [])}
end
def new(*args, &block)
@@ -29,7 +29,7 @@ def create!(*args, &block)
end
def respond_to?(method, include_private = false)
- return true if @relation.respond_to?(method, include_private) || Array.method_defined?(method)
+ return true if arel.respond_to?(method, include_private) || Array.method_defined?(method)
if match = DynamicFinderMatch.match(method)
return true if @klass.send(:all_attributes_exists?, match.attribute_names)
@@ -43,33 +43,35 @@ def respond_to?(method, include_private = false)
def to_a
return @records if loaded?
- find_with_associations = @eager_load_associations.any? || references_eager_loaded_tables?
+ find_with_associations = @eager_load_values.any? || (@includes_values.any? && references_eager_loaded_tables?)
@records = if find_with_associations
begin
@klass.send(:find_with_associations, {
- :select => @relation.send(:select_clauses).join(', '),
- :joins => @relation.joins(relation),
- :group => @relation.send(:group_clauses).join(', '),
+ :select => arel.send(:select_clauses).join(', '),
+ :joins => arel.joins(arel),
+ :group => arel.send(:group_clauses).join(', '),
:order => order_clause,
:conditions => where_clause,
- :limit => @relation.taken,
- :offset => @relation.skipped,
- :from => (@relation.send(:from_clauses) if @relation.send(:sources).present?)
+ :limit => arel.taken,
+ :offset => arel.skipped,
+ :from => (arel.send(:from_clauses) if arel.send(:sources).present?)
},
- ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, @eager_load_associations + @includes_associations, nil))
+ ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, @eager_load_values + @includes_values, nil))
rescue ThrowResult
[]
end
else
- @klass.find_by_sql(@relation.to_sql)
+ @klass.find_by_sql(arel.to_sql)
end
- preload = @preload_associations
- preload += @includes_associations unless find_with_associations
+ preload = @preload_values
+ preload += @includes_values unless find_with_associations
preload.each {|associations| @klass.send(:preload_associations, @records, associations) }
- @records.each { |record| record.readonly! } if @readonly
+ # @readonly_value is true only if set explicity. @implicit_readonly is true if there are JOINS and no explicit SELECT.
+ readonly = @readonly_value.nil? ? @implicit_readonly : @readonly_value
+ @records.each { |record| record.readonly! } if readonly
@loaded = true
@records
@@ -97,7 +99,7 @@ def many?
if block_given?
to_a.many? { |*block_args| yield(*block_args) }
else
- @relation.send(:taken).present? ? to_a.many? : size > 1
+ arel.send(:taken).present? ? to_a.many? : size > 1
end
end
@@ -107,7 +109,7 @@ def destroy_all
end
def delete_all
- @relation.delete.tap { reset }
+ arel.delete.tap { reset }
end
def delete(id_or_array)
@@ -124,28 +126,24 @@ def reload
end
def reset
- @first = @last = @to_sql = @order_clause = @scope_for_create = nil
+ @first = @last = @to_sql = @order_clause = @scope_for_create = @arel = nil
@records = []
self
end
- def table
- @table ||= Arel::Table.new(@klass.table_name, :engine => @klass.active_relation_engine)
- end
-
def primary_key
@primary_key ||= table[@klass.primary_key]
end
def to_sql
- @to_sql ||= @relation.to_sql
+ @to_sql ||= arel.to_sql
end
protected
def method_missing(method, *args, &block)
- if @relation.respond_to?(method)
- @relation.send(method, *args, &block)
+ if arel.respond_to?(method)
+ arel.send(method, *args, &block)
elsif Array.method_defined?(method)
to_a.send(method, *args, &block)
elsif match = DynamicFinderMatch.match(method)
@@ -168,23 +166,23 @@ def with_create_scope
def scope_for_create
@scope_for_create ||= begin
- @create_with_attributes || wheres.inject({}) do |hash, where|
+ @create_with_value || wheres.inject({}) do |hash, where|
hash[where.operand1.name] = where.operand2.value if where.is_a?(Arel::Predicates::Equality)
hash
end
end
end
def where_clause(join_string = " AND ")
- @relation.send(:where_clauses).join(join_string)
+ arel.send(:where_clauses).join(join_string)
end
def order_clause
- @order_clause ||= @relation.send(:order_clauses).join(', ')
+ @order_clause ||= arel.send(:order_clauses).join(', ')
end
def references_eager_loaded_tables?
- joined_tables = (tables_in_string(@relation.joins(relation)) + [table.name, table.table_alias]).compact.uniq
+ joined_tables = (tables_in_string(arel.joins(arel)) + [table.name, table.table_alias]).compact.uniq
(tables_in_string(to_sql) - joined_tables).any?
end
View
14 activerecord/lib/active_record/relation/calculation_methods.rb
@@ -25,7 +25,7 @@ def calculate(operation, column_name, options = {})
operation = operation.to_s.downcase
if operation == "count"
- joins = @relation.joins(relation)
+ joins = arel.joins(arel)
if joins.present? && joins =~ /LEFT OUTER/i
distinct = true
column_name = @klass.primary_key if column_name == :all
@@ -40,7 +40,7 @@ def calculate(operation, column_name, options = {})
distinct = options[:distinct] || distinct
column_name = :all if column_name.blank? && operation == "count"
- if @relation.send(:groupings).any?
+ if arel.send(:groupings).any?
return execute_grouped_calculation(operation, column_name)
else
return execute_simple_calculation(operation, column_name, distinct)
@@ -63,7 +63,7 @@ def execute_simple_calculation(operation, column_name, distinct) #:nodoc:
end
def execute_grouped_calculation(operation, column_name) #:nodoc:
- group_attr = @relation.send(:groupings).first.value
+ group_attr = arel.send(:groupings).first.value
association = @klass.reflect_on_association(group_attr.to_sym)
associated = association && association.macro == :belongs_to # only count belongs_to associations
group_field = associated ? association.primary_key_name : group_attr
@@ -165,12 +165,8 @@ def type_cast_using_column(value, column)
column ? column.type_cast(value) : value
end
- def get_projection_name_from_chained_relations(relation = @relation)
- if relation.respond_to?(:projections) && relation.projections.present?
- relation.send(:select_clauses).join(', ')
- elsif relation.respond_to?(:relation)
- get_projection_name_from_chained_relations(relation.relation)
- end
+ def get_projection_name_from_chained_relations
+ @select_values.join(", ") if @select_values.present?
end
end
View
8 activerecord/lib/active_record/relation/finder_methods.rb
@@ -93,15 +93,15 @@ def find_some(ids)
result = where(primary_key.in(ids)).all
expected_size =
- if @relation.taken && ids.size > @relation.taken
- @relation.taken
+ if arel.taken && ids.size > arel.taken
+ arel.taken
else
ids.size
end
# 11 ids with limit 3, offset 9 should give 2 results.
- if @relation.skipped && (ids.size - @relation.skipped < expected_size)
- expected_size = ids.size - @relation.skipped
+ if arel.skipped && (ids.size - arel.skipped < expected_size)
+ expected_size = ids.size - arel.skipped
end
if result.size == expected_size
View
165 activerecord/lib/active_record/relation/query_methods.rb
@@ -1,116 +1,125 @@
module ActiveRecord
module QueryMethods
-
- def preload(*associations)
- spawn.tap {|r| r.preload_associations += Array.wrap(associations) }
- end
-
- def includes(*associations)
- spawn.tap {|r| r.includes_associations += Array.wrap(associations) }
- end
-
- def eager_load(*associations)
- spawn.tap {|r| r.eager_load_associations += Array.wrap(associations) }
- end
-
- def readonly(status = true)
- spawn.tap {|r| r.readonly = status }
- end
-
- def create_with(attributes = {})
- spawn.tap {|r| r.create_with_attributes = attributes }
- end
-
- def select(selects)
- if selects.present?
- relation = spawn(@relation.project(selects))
- relation.readonly = @relation.joins(relation).present? ? false : @readonly
- relation
- else
- spawn
+ extend ActiveSupport::Concern
+
+ included do
+ (ActiveRecord::Relation::ASSOCIATION_METHODS + ActiveRecord::Relation::MULTI_VALUE_METHODS).each do |query_method|
+ attr_accessor :"#{query_method}_values"
+
+ class_eval <<-CEVAL
+ def #{query_method}(*args)
+ spawn.tap do |new_relation|
+ new_relation.#{query_method}_values ||= []
+ value = args.size > 1 ? [args] : Array.wrap(args)
+ new_relation.#{query_method}_values += value
+ end
+ end
+ CEVAL
end
- end
-
- def from(from)
- from.present? ? spawn(@relation.from(from)) : spawn
- end
- def having(*args)
- return spawn if args.blank?
+ ActiveRecord::Relation::SINGLE_VALUE_METHODS.each do |query_method|
+ attr_accessor :"#{query_method}_value"
- if [String, Hash, Array].include?(args.first.class)
- havings = @klass.send(:merge_conditions, args.size > 1 ? Array.wrap(args) : args.first)
- else
- havings = args.first
+ class_eval <<-CEVAL
+ def #{query_method}(value = true)
+ spawn.tap do |new_relation|
+ new_relation.#{query_method}_value = value
+ end
+ end
+ CEVAL
end
-
- spawn(@relation.having(havings))
- end
-
- def group(groups)
- groups.present? ? spawn(@relation.group(groups)) : spawn
- end
-
- def order(orders)
- orders.present? ? spawn(@relation.order(orders)) : spawn
end
def lock(locks = true)
+ relation = spawn
case locks
- when String
- spawn(@relation.lock(locks))
- when TrueClass, NilClass
- spawn(@relation.lock)
+ when String, TrueClass, NilClass
+ spawn.tap {|new_relation| new_relation.lock_value = locks || true }
else
- spawn
+ spawn.tap {|new_relation| new_relation.lock_value = false }
end
end
def reverse_order
relation = spawn
relation.instance_variable_set(:@orders, nil)
- order_clause = @relation.send(:order_clauses).join(', ')
+ order_clause = arel.send(:order_clauses).join(', ')
if order_clause.present?
relation.order(reverse_sql_order(order_clause))
else
relation.order("#{@klass.table_name}.#{@klass.primary_key} DESC")
end
end
- def limit(limits)
- limits.present? ? spawn(@relation.take(limits)) : spawn
+ def arel
+ @arel ||= build_arel
end
- def offset(offsets)
- offsets.present? ? spawn(@relation.skip(offsets)) : spawn
- end
+ def build_arel
+ arel = table
- def on(join)
- spawn(@relation.on(join))
- end
+ @joins_values.each do |j|
+ next if j.blank?
- def joins(join, join_type = nil)
- return spawn if join.blank?
+ @implicit_readonly = true
- join_relation = case join
- when String
- @relation.join(join)
- when Hash, Array, Symbol
- if @klass.send(:array_of_strings?, join)
- @relation.join(join.join(' '))
+ case j
+ when Relation::JoinOperation
+ arel = arel.join(j.relation, j.join_class).on(j.on)
+ when Hash, Array, Symbol
+ if @klass.send(:array_of_strings?, j)
+ arel = arel.join(j.join(' '))
+ else
+ arel = arel.join(@klass.send(:build_association_joins, j))
+ end
else
- @relation.join(@klass.send(:build_association_joins, join))
+ arel = arel.join(j)
end
- else
- @relation.join(join, join_type)
end
- spawn(join_relation).tap { |r| r.readonly = true }
+ @where_values.each do |where|
+ if conditions = build_where(where)
+ arel = conditions.is_a?(String) ? arel.where(conditions) : arel.where(*conditions)
+ end
+ end
+
+ @having_values.each do |where|
+ if conditions = build_where(where)
+ arel = conditions.is_a?(String) ? arel.having(conditions) : arel.having(*conditions)
+ end
+ end
+
+ arel = arel.take(@limit_value) if @limit_value.present?
+ arel = arel.skip(@offset_value) if @offset_value.present?
+
+ @group_values.each do |g|
+ arel = arel.group(g) if g.present?
+ end
+
+ @order_values.each do |o|
+ arel = arel.order(o) if o.present?
+ end
+
+ @select_values.each do |s|
+ @implicit_readonly = false
+ arel = arel.project(s) if s.present?
+ end
+
+ arel = arel.from(@from_value) if @from_value.present?
+
+ case @lock_value
+ when TrueClass
+ arel = arel.lock
+ when String
+ arel = arel.lock(@lock_value)
+ end
+
+ arel
end
- def where(*args)
- return spawn if args.blank?
+ def build_where(*args)
+ return if args.blank?
builder = PredicateBuilder.new(Arel::Sql::Engine.new(@klass))
@@ -124,7 +133,7 @@ def where(*args)
args.first
end
- conditions.is_a?(String) ? spawn(@relation.where(conditions)) : spawn(@relation.where(*conditions))
+ conditions
end
private
View
89 activerecord/lib/active_record/relation/spawn_methods.rb
@@ -1,82 +1,75 @@
module ActiveRecord
module SpawnMethods
- def spawn(relation = @relation)
- relation = Relation.new(@klass, relation)
- relation.readonly = @readonly
- relation.preload_associations = @preload_associations
- relation.eager_load_associations = @eager_load_associations
- relation.includes_associations = @includes_associations
- relation.create_with_attributes = @create_with_attributes
- relation.table = table
+ def spawn(arel_table = self.table)
+ relation = Relation.new(@klass, arel_table)
+
+ (Relation::ASSOCIATION_METHODS + Relation::MULTI_VALUE_METHODS).each do |query_method|
+ relation.send(:"#{query_method}_values=", send(:"#{query_method}_values"))
+ end
+
+ Relation::SINGLE_VALUE_METHODS.each do |query_method|
+ relation.send(:"#{query_method}_value=", send(:"#{query_method}_value"))
+ end
+
relation
end
def merge(r)
raise ArgumentError, "Cannot merge a #{r.klass.name} relation with #{@klass.name} relation" if r.klass != @klass
- merged_relation = spawn(table).eager_load(r.eager_load_associations).preload(r.preload_associations).includes(r.includes_associations)
- merged_relation.readonly = r.readonly
-
- [self.relation, r.relation].each do |arel|
- merged_relation = merged_relation.
- joins(arel.joins(arel)).
- group(arel.groupings).
- limit(arel.taken).
- offset(arel.skipped).
- select(arel.send(:select_clauses)).
- from(arel.sources).
- having(arel.havings).
- lock(arel.locked)
- end
+ merged_relation = spawn.eager_load(r.eager_load_values).preload(r.preload_values).includes(r.includes_values)
+
+ merged_relation.readonly_value = r.readonly_value unless merged_relation.readonly_value
+ merged_relation.limit_value = r.limit_value unless merged_relation.limit_value
+ merged_relation.lock_value = r.lock_value unless merged_relation.lock_value
+
+ merged_relation = merged_relation.
+ joins(r.joins_values).
+ group(r.group_values).
+ offset(r.offset_value).
+ select(r.select_values).
+ from(r.from_value).
+ having(r.having_values)
- relation_order = r.send(:order_clause)
- merged_order = relation_order.present? ? relation_order : order_clause
- merged_relation = merged_relation.order(merged_order)
+ relation_order = r.order_values
+ merged_order = relation_order.present? ? relation_order : order_values
+ merged_relation.order_values = merged_order
- merged_relation.create_with_attributes = @create_with_attributes
+ merged_relation.create_with_value = @create_with_value
- if @create_with_attributes && r.create_with_attributes
- merged_relation.create_with_attributes = @create_with_attributes.merge(r.create_with_attributes)
+ if @create_with_value && r.create_with_value
+ merged_relation.create_with_value = @create_with_value.merge(r.create_with_value)
else
- merged_relation.create_with_attributes = r.create_with_attributes || @create_with_attributes
+ merged_relation.create_with_value = r.create_with_value || @create_with_value
end
- merged_wheres = @relation.wheres
+ merged_wheres = @where_values
- r.wheres.each do |w|
+ r.where_values.each do |w|
if w.is_a?(Arel::Predicates::Equality)
merged_wheres = merged_wheres.reject {|p| p.is_a?(Arel::Predicates::Equality) && p.operand1.name == w.operand1.name }
end
merged_wheres << w
end
- merged_relation.where(*merged_wheres)
+ merged_relation.where_values = merged_wheres
+
+ merged_relation
end
alias :& :merge
def except(*skips)
result = Relation.new(@klass, table)
- result.table = table
- [:eager_load, :preload, :includes].each do |load_method|
- result = result.send(load_method, send(:"#{load_method}_associations"))
+ (Relation::ASSOCIATION_METHODS + Relation::MULTI_VALUE_METHODS).each do |method|
+ result.send(:"#{method}_values=", send(:"#{method}_values")) unless skips.include?(method)
end
- result.readonly = self.readonly unless skips.include?(:readonly)
- result.create_with_attributes = @create_with_attributes unless skips.include?(:create_with)
-
- result = result.joins(@relation.joins(@relation)) unless skips.include?(:joins)
- result = result.group(@relation.groupings) unless skips.include?(:group)
- result = result.limit(@relation.taken) unless skips.include?(:limit)
- result = result.offset(@relation.skipped) unless skips.include?(:offset)
- result = result.select(@relation.send(:select_clauses)) unless skips.include?(:select)
- result = result.from(@relation.sources) unless skips.include?(:from)
- result = result.order(order_clause) unless skips.include?(:order)
- result = result.where(*@relation.wheres) unless skips.include?(:where)
- result = result.having(*@relation.havings) unless skips.include?(:having)
- result = result.lock(@relation.locked) unless skips.include?(:lock)
+ Relation::SINGLE_VALUE_METHODS.each do |method|
+ result.send(:"#{method}_value=", send(:"#{method}_value")) unless skips.include?(method)
+ end
result
end

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