diff options
Diffstat (limited to 'activerecord/lib/active_record/relation')
3 files changed, 149 insertions, 39 deletions
diff --git a/activerecord/lib/active_record/relation/batches.rb b/activerecord/lib/active_record/relation/batches.rb index 49b01909c6..29fc150b3d 100644 --- a/activerecord/lib/active_record/relation/batches.rb +++ b/activerecord/lib/active_record/relation/batches.rb @@ -52,7 +52,9 @@ module ActiveRecord records.each { |record| yield record } end else - enum_for :find_each, options + enum_for :find_each, options do + options[:start] ? where(table[primary_key].gteq(options[:start])).size : size + end end end @@ -64,6 +66,16 @@ module ActiveRecord # group.each { |person| person.party_all_night! } # end # + # If you do not provide a block to #find_in_batches, it will return an Enumerator + # for chaining with other methods: + # + # Person.find_in_batches.with_index do |group, batch| + # puts "Processing group ##{batch}" + # group.each(&:recover_from_last_night!) + # end + # + # To be yielded each record one by one, use #find_each instead. + # # ==== Options # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000. # * <tt>:start</tt> - Specifies the starting point for the batch processing. @@ -88,30 +100,33 @@ module ActiveRecord options.assert_valid_keys(:start, :batch_size) relation = self + start = options[:start] + batch_size = options[:batch_size] || 1000 + + unless block_given? + return to_enum(:find_in_batches, options) do + total = start ? where(table[primary_key].gteq(start)).size : size + (total - 1).div(batch_size) + 1 + end + end if logger && (arel.orders.present? || arel.taken.present?) logger.warn("Scoped order and limit are ignored, it's forced to be batch order and batch size") end - start = options.delete(:start) - batch_size = options.delete(:batch_size) || 1000 - relation = relation.reorder(batch_order).limit(batch_size) records = start ? relation.where(table[primary_key].gteq(start)).to_a : relation.to_a while records.any? records_size = records.size primary_key_offset = records.last.id + raise "Primary key not included in the custom select clause" unless primary_key_offset yield records break if records_size < batch_size - if primary_key_offset - records = relation.where(table[primary_key].gt(primary_key_offset)).to_a - else - raise "Primary key not included in the custom select clause" - end + records = relation.where(table[primary_key].gt(primary_key_offset)).to_a end end diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 4984dbd277..7099bdd285 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -127,9 +127,9 @@ module ActiveRecord # def first(limit = nil) if limit - find_first_with_limit(limit) + find_nth_with_limit(offset_value, limit) else - find_first + find_nth(:first, offset_value) end end @@ -172,6 +172,86 @@ module ActiveRecord last or raise RecordNotFound end + # Find the second record. + # If no order is defined it will order by primary key. + # + # Person.second # returns the second object fetched by SELECT * FROM people + # Person.offset(3).second # returns the second object from OFFSET 3 (which is OFFSET 4) + # Person.where(["user_name = :u", { u: user_name }]).second + def second + find_nth(:second, offset_value ? offset_value + 1 : 1) + end + + # Same as +second+ but raises <tt>ActiveRecord::RecordNotFound</tt> if no record + # is found. + def second! + second or raise RecordNotFound + end + + # Find the third record. + # If no order is defined it will order by primary key. + # + # Person.third # returns the third object fetched by SELECT * FROM people + # Person.offset(3).third # returns the third object from OFFSET 3 (which is OFFSET 5) + # Person.where(["user_name = :u", { u: user_name }]).third + def third + find_nth(:third, offset_value ? offset_value + 2 : 2) + end + + # Same as +third+ but raises <tt>ActiveRecord::RecordNotFound</tt> if no record + # is found. + def third! + third or raise RecordNotFound + end + + # Find the fourth record. + # If no order is defined it will order by primary key. + # + # Person.fourth # returns the fourth object fetched by SELECT * FROM people + # Person.offset(3).fourth # returns the fourth object from OFFSET 3 (which is OFFSET 6) + # Person.where(["user_name = :u", { u: user_name }]).fourth + def fourth + find_nth(:fourth, offset_value ? offset_value + 3 : 3) + end + + # Same as +fourth+ but raises <tt>ActiveRecord::RecordNotFound</tt> if no record + # is found. + def fourth! + fourth or raise RecordNotFound + end + + # Find the fifth record. + # If no order is defined it will order by primary key. + # + # Person.fifth # returns the fifth object fetched by SELECT * FROM people + # Person.offset(3).fifth # returns the fifth object from OFFSET 3 (which is OFFSET 7) + # Person.where(["user_name = :u", { u: user_name }]).fifth + def fifth + find_nth(:fifth, offset_value ? offset_value + 4 : 4) + end + + # Same as +fifth+ but raises <tt>ActiveRecord::RecordNotFound</tt> if no record + # is found. + def fifth! + fifth or raise RecordNotFound + end + + # Find the forty-second record. Also known as accessing "the reddit". + # If no order is defined it will order by primary key. + # + # Person.forty_two # returns the forty-second object fetched by SELECT * FROM people + # Person.offset(3).forty_two # returns the fifth object from OFFSET 3 (which is OFFSET 44) + # Person.where(["user_name = :u", { u: user_name }]).forty_two + def forty_two + find_nth(:forty_two, offset_value ? offset_value + 41 : 41) + end + + # Same as +forty_two+ but raises <tt>ActiveRecord::RecordNotFound</tt> if no record + # is found. + def forty_two! + forty_two or raise RecordNotFound + end + # Returns +true+ if a record exists in the table that matches the +id+ or # conditions given, or +false+ otherwise. The argument can take six forms: # @@ -231,9 +311,9 @@ module ActiveRecord conditions = " [#{conditions}]" if conditions if Array(ids).size == 1 - error = "Couldn't find #{@klass.name} with #{primary_key}=#{ids}#{conditions}" + error = "Couldn't find #{@klass.name} with '#{primary_key}'=#{ids}#{conditions}" else - error = "Couldn't find all #{@klass.name.pluralize} with IDs " + error = "Couldn't find all #{@klass.name.pluralize} with '#{primary_key}': " error << "(#{ids.join(", ")})#{conditions} (found #{result_size} results, but was looking for #{expected_size})" end @@ -267,7 +347,15 @@ module ActiveRecord end def construct_relation_for_association_calculations - apply_join_dependency(self, construct_join_dependency(arel.froms.first)) + from = arel.froms.first + if Arel::Table === from + apply_join_dependency(self, construct_join_dependency) + else + # FIXME: as far as I can tell, `from` will always be an Arel::Table. + # There are no tests that test this branch, but presumably it's + # possible for `from` to be a list? + apply_join_dependency(self, construct_join_dependency(from)) + end end def apply_join_dependency(relation, join_dependency) @@ -364,19 +452,19 @@ module ActiveRecord end end - def find_first + def find_nth(ordinal, offset) if loaded? - @records.first + @records.send(ordinal) else - @first ||= find_first_with_limit(1).first + @offsets[offset] ||= find_nth_with_limit(offset, 1).first end end - def find_first_with_limit(limit) + def find_nth_with_limit(offset, limit) if order_values.empty? && primary_key - order(arel_table[primary_key].asc).limit(limit).to_a + order(arel_table[primary_key].asc).limit(limit).offset(offset).to_a else - limit(limit).to_a + limit(limit).offset(offset).to_a end end diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index 979216bee7..5d38f0dce8 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -120,6 +120,9 @@ module ActiveRecord # Will throw an error, but this will work: # # User.includes(:posts).where('posts.name = ?', 'example').references(:posts) + # + # Note that +includes+ works with association names while +references+ needs + # the actual table name. def includes(*args) check_if_method_has_arguments!(:includes, args) spawn.includes!(*args) @@ -163,24 +166,26 @@ module ActiveRecord self end - # Used to indicate that an association is referenced by an SQL string, and should - # therefore be JOINed in any query rather than loaded separately. + # Use to indicate that the given +table_names+ are referenced by an SQL string, + # and should therefore be JOINed in any query rather than loaded separately. + # This method only works in conjuction with +includes+. + # See #includes for more details. # # User.includes(:posts).where("posts.name = 'foo'") # # => Doesn't JOIN the posts table, resulting in an error. # # User.includes(:posts).where("posts.name = 'foo'").references(:posts) # # => Query now knows the string references posts, so adds a JOIN - def references(*args) - check_if_method_has_arguments!(:references, args) - spawn.references!(*args) + def references(*table_names) + check_if_method_has_arguments!(:references, table_names) + spawn.references!(*table_names) end - def references!(*args) # :nodoc: - args.flatten! - args.map!(&:to_s) + def references!(*table_names) # :nodoc: + table_names.flatten! + table_names.map!(&:to_s) - self.references_values |= args + self.references_values |= table_names self end @@ -234,7 +239,9 @@ module ActiveRecord def select!(*fields) # :nodoc: fields.flatten! - + fields.map! do |field| + klass.attribute_alias?(field) ? klass.attribute_alias(field) : field + end self.select_values += fields self end @@ -817,11 +824,12 @@ module ActiveRecord end # Returns the Arel object associated with the relation. - def arel + def arel # :nodoc: @arel ||= build_arel end - # Like #arel, but ignores the default scope of the model. + private + def build_arel arel = Arel::SelectManager.new(table.engine, table) @@ -847,8 +855,6 @@ module ActiveRecord arel end - private - def symbol_unscoping(scope) if !VALID_UNSCOPING_VALUES.include?(scope) raise ArgumentError, "Called unscope() with invalid unscoping argument ':#{scope}'. Valid arguments are :#{VALID_UNSCOPING_VALUES.to_a.join(", :")}." @@ -876,8 +882,6 @@ module ActiveRecord when Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual subrelation = (rel.left.kind_of?(Arel::Attributes::Attribute) ? rel.left : rel.right) subrelation.name == target_value - else - raise "unscope(where: #{target_value.inspect}) failed: unscoping #{rel.class} is unimplemented." end end @@ -987,9 +991,10 @@ module ActiveRecord def build_select(arel, selects) if !selects.empty? - arel.project(*selects) - elsif from_value - arel.project(Arel.star) + expanded_select = selects.map do |field| + columns_hash.key?(field.to_s) ? arel_table[field] : field + end + arel.project(*expanded_select) else arel.project(@klass.arel_table[Arel.star]) end @@ -1045,9 +1050,11 @@ module ActiveRecord order_args.map! do |arg| case arg when Symbol + arg = klass.attribute_alias(arg) if klass.attribute_alias?(arg) table[arg].asc when Hash arg.map { |field, dir| + field = klass.attribute_alias(field) if klass.attribute_alias?(field) table[field].send(dir) } else |