diff options
Diffstat (limited to 'activerecord/lib/active_record/relation')
5 files changed, 129 insertions, 26 deletions
diff --git a/activerecord/lib/active_record/relation/batches.rb b/activerecord/lib/active_record/relation/batches.rb index ec1176e3dd..2fd89882ff 100644 --- a/activerecord/lib/active_record/relation/batches.rb +++ b/activerecord/lib/active_record/relation/batches.rb @@ -62,7 +62,7 @@ module ActiveRecord start = options.delete(:start).to_i batch_size = options.delete(:batch_size) || 1000 - relation = relation.except(:order).order(batch_order).limit(batch_size) + relation = relation.reorder(batch_order).limit(batch_size) records = relation.where(table[primary_key].gteq(start)).all while records.any? diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb index 9a7ff87e88..0f57e9831d 100644 --- a/activerecord/lib/active_record/relation/calculations.rb +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -166,6 +166,23 @@ module ActiveRecord 0 end + # This method is designed to perform select by a single column as direct SQL query + # Returns <tt>Array</tt> with values of the specified column name + # The values has same data type as column. + # + # Examples: + # + # Person.pluck(:id) # SELECT people.id FROM people + # Person.uniq.pluck(:role) # SELECT DISTINCT role FROM people + # Person.where(:confirmed => true).limit(5).pluck(:id) + # + def pluck(column_name) + scope = self.select(column_name) + self.connection.select_values(scope.to_sql).map! do |value| + type_cast_using_column(value, column_for(column_name)) + end + end + private def perform_calculation(operation, column_name, options = {}) @@ -223,7 +240,7 @@ module ActiveRecord query_builder = relation.arel end - type_cast_calculated_value(@klass.connection.select_value(query_builder.to_sql), column_for(column_name), operation) + type_cast_calculated_value(@klass.connection.select_value(query_builder), column_for(column_name), operation) end def execute_grouped_calculation(operation, column_name, distinct) #:nodoc: @@ -259,7 +276,7 @@ module ActiveRecord relation = except(:group).group(group.join(',')) relation.select_values = select_values - calculated_data = @klass.connection.select_all(relation.to_sql) + calculated_data = @klass.connection.select_all(relation) if association key_ids = calculated_data.collect { |row| row[group_aliases.first] } diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 8cef4e5554..3c8e0f2052 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -114,7 +114,7 @@ module ActiveRecord def first(*args) if args.any? if args.first.kind_of?(Integer) || (loaded? && !args.first.kind_of?(Hash)) - to_a.first(*args) + limit(*args).to_a else apply_finder_options(args.first).first end @@ -134,7 +134,11 @@ module ActiveRecord def last(*args) if args.any? if args.first.kind_of?(Integer) || (loaded? && !args.first.kind_of?(Hash)) - to_a.last(*args) + if order_values.empty? && reorder_value.nil? + order("#{primary_key} DESC").limit(*args).reverse + else + to_a.last(*args) + end else apply_finder_options(args.first).last end @@ -180,12 +184,14 @@ module ActiveRecord # Person.exists?(:name => "David") # Person.exists?(['name LIKE ?', "%#{query}%"]) # Person.exists? - def exists?(id = nil) + def exists?(id = false) + return false if id.nil? + id = id.id if ActiveRecord::Base === id join_dependency = construct_join_dependency_for_association_find relation = construct_relation_for_association_find(join_dependency) - relation = relation.except(:select).select("1").limit(1) + relation = relation.except(:select, :order).select("1").limit(1) case id when Array, Hash @@ -193,8 +199,8 @@ module ActiveRecord else relation = relation.where(table[primary_key].eq(id)) if id end - - connection.select_value(relation.to_sql, "#{name} Exists") ? true : false + + connection.select_value(relation, "#{name} Exists") ? true : false end protected @@ -202,7 +208,7 @@ module ActiveRecord def find_with_associations join_dependency = construct_join_dependency_for_association_find relation = construct_relation_for_association_find(join_dependency) - rows = connection.select_all(relation.to_sql, 'SQL', relation.bind_values) + rows = connection.select_all(relation, 'SQL', relation.bind_values) join_dependency.instantiate(rows) rescue ThrowResult [] diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb index 2814771002..a789f48725 100644 --- a/activerecord/lib/active_record/relation/predicate_builder.rb +++ b/activerecord/lib/active_record/relation/predicate_builder.rb @@ -19,24 +19,26 @@ module ActiveRecord case value when ActiveRecord::Relation - value.select_values = [value.klass.arel_table['id']] if value.select_values.empty? + value = value.select(value.klass.arel_table[value.klass.primary_key]) if value.select_values.empty? attribute.in(value.arel.ast) when Array, ActiveRecord::Associations::CollectionProxy - values = value.to_a.map { |x| - x.is_a?(ActiveRecord::Base) ? x.id : x - } + values = value.to_a.map {|x| x.is_a?(ActiveRecord::Base) ? x.id : x} + ranges, values = values.partition {|v| v.is_a?(Range) || v.is_a?(Arel::Relation)} + + array_predicates = ranges.map {|range| attribute.in(range)} if values.include?(nil) values = values.compact if values.empty? - attribute.eq nil + array_predicates << attribute.eq(nil) else - attribute.in(values.compact).or attribute.eq(nil) + array_predicates << attribute.in(values.compact).or(attribute.eq(nil)) end else - attribute.in(values) + array_predicates << attribute.in(values) end + array_predicates.inject {|composite, predicate| composite.or(predicate)} when Range, Arel::Relation attribute.in(value) when ActiveRecord::Base diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index 3a7b245c51..c281bead0d 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -9,7 +9,8 @@ module ActiveRecord :select_values, :group_values, :order_values, :joins_values, :where_values, :having_values, :bind_values, :limit_value, :offset_value, :lock_value, :readonly_value, :create_with_value, - :from_value, :reorder_value, :reverse_order_value + :from_value, :reorder_value, :reverse_order_value, + :uniq_value def includes(*args) args.reject! {|a| a.blank? } @@ -37,6 +38,35 @@ module ActiveRecord relation end + # Works in two unique ways. + # + # First: takes a block so it can be used just like Array#select. + # + # Model.scoped.select { |m| m.field == value } + # + # This will build an array of objects from the database for the scope, + # converting them into an array and iterating through them using Array#select. + # + # Second: Modifies the SELECT statement for the query so that only certain + # fields are retrieved: + # + # >> Model.select(:field) + # => [#<Model field:value>] + # + # Although in the above example it looks as though this method returns an + # array, it actually returns a relation object and can have other query + # methods appended to it, such as the other methods in ActiveRecord::QueryMethods. + # + # This method will also take multiple parameters: + # + # >> Model.select(:field, :other_field, :and_one_more) + # => [#<Model field: "value", other_field: "value", and_one_more: "value">] + # + # Any attributes that do not have fields retrieved by a select + # will return `nil` when the getter method for that attribute is used: + # + # >> Model.select(:field).first.other_field + # => nil def select(value = Proc.new) if block_given? to_a.select {|*block_args| value.call(*block_args) } @@ -147,6 +177,58 @@ module ActiveRecord relation end + # Specifies whether the records should be unique or not. For example: + # + # User.select(:name) + # # => Might return two records with the same name + # + # User.select(:name).uniq + # # => Returns 1 record per unique name + # + # User.select(:name).uniq.uniq(false) + # # => You can also remove the uniqueness + def uniq(value = true) + relation = clone + relation.uniq_value = value + relation + end + + # Used to extend a scope with additional methods, either through + # a module or through a block provided. + # + # The object returned is a relation, which can be further extended. + # + # === Using a module + # + # module Pagination + # def page(number) + # # pagination code goes here + # end + # end + # + # scope = Model.scoped.extending(Pagination) + # scope.page(params[:page]) + # + # You can also pass a list of modules: + # + # scope = Model.scoped.extending(Pagination, SomethingElse) + # + # === Using a block + # + # scope = Model.scoped.extending do + # def page(number) + # # pagination code goes here + # end + # end + # scope.page(params[:page]) + # + # You can also use a block and a module list: + # + # scope = Model.scoped.extending(Pagination) do + # def per_page(number) + # # pagination code goes here + # end + # end def extending(*modules) modules << Module.new(&Proc.new) if block_given? @@ -187,6 +269,7 @@ module ActiveRecord build_select(arel, @select_values.uniq) + arel.distinct(@uniq_value) arel.from(@from_value) if @from_value arel.lock(@lock_value) if @lock_value @@ -254,12 +337,12 @@ module ActiveRecord association_joins = buckets['association_join'] || [] stashed_association_joins = buckets['stashed_join'] || [] - join_nodes = buckets['join_node'] || [] + join_nodes = (buckets['join_node'] || []).uniq string_joins = (buckets['string_join'] || []).map { |x| x.strip }.uniq - join_list = custom_join_ast(manager, string_joins) + join_list = join_nodes + custom_join_ast(manager, string_joins) join_dependency = ActiveRecord::Associations::JoinDependency.new( @klass, @@ -267,10 +350,6 @@ module ActiveRecord join_list ) - join_nodes.each do |join| - join_dependency.alias_tracker.aliased_name_for(join.left.name.downcase) - end - join_dependency.graft(*stashed_association_joins) @implicit_readonly = true unless association_joins.empty? && stashed_association_joins.empty? @@ -280,7 +359,6 @@ module ActiveRecord association.join_to(manager) end - manager.join_sources.concat join_nodes.uniq manager.join_sources.concat join_list manager @@ -312,7 +390,7 @@ module ActiveRecord when String, Symbol o.to_s.split(',').collect do |s| s.strip! - (s if s =~ /\(/) || s.gsub!(/\sasc\Z/i, ' DESC') || s.gsub!(/\sdesc\Z/i, ' ASC') || s.concat(' DESC') + s.gsub!(/\sasc\Z/i, ' DESC') || s.gsub!(/\sdesc\Z/i, ' ASC') || s.concat(' DESC') end else o |