diff options
Diffstat (limited to 'activerecord/lib/active_record/persistence.rb')
| -rw-r--r-- | activerecord/lib/active_record/persistence.rb | 139 |
1 files changed, 136 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb index fbbf9082cc..a13b0d0181 100644 --- a/activerecord/lib/active_record/persistence.rb +++ b/activerecord/lib/active_record/persistence.rb @@ -71,6 +71,132 @@ module ActiveRecord klass.allocate.init_with("attributes" => attributes, "new_record" => false, &block) end + # Updates an object (or multiple objects) and saves it to the database, if validations pass. + # The resulting object is returned whether the object was saved successfully to the database or not. + # + # ==== Parameters + # + # * +id+ - This should be the id or an array of ids to be updated. + # * +attributes+ - This should be a hash of attributes or an array of hashes. + # + # ==== Examples + # + # # Updates one record + # Person.update(15, user_name: "Samuel", group: "expert") + # + # # Updates multiple records + # people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } } + # Person.update(people.keys, people.values) + # + # # Updates multiple records from the result of a relation + # people = Person.where(group: "expert") + # people.update(group: "masters") + # + # Note: Updating a large number of records will run an UPDATE + # query for each record, which may cause a performance issue. + # When running callbacks is not needed for each record update, + # it is preferred to use {update_all}[rdoc-ref:Relation#update_all] + # for updating all records in a single query. + def update(id = :all, attributes) + if id.is_a?(Array) + id.map { |one_id| find(one_id) }.each_with_index { |object, idx| + object.update(attributes[idx]) + } + elsif id == :all + all.each { |record| record.update(attributes) } + else + if ActiveRecord::Base === id + raise ArgumentError, + "You are passing an instance of ActiveRecord::Base to `update`. " \ + "Please pass the id of the object by calling `.id`." + end + object = find(id) + object.update(attributes) + object + end + end + + # Destroy an object (or multiple objects) that has the given id. The object is instantiated first, + # therefore all callbacks and filters are fired off before the object is deleted. This method is + # less efficient than #delete but allows cleanup methods and other actions to be run. + # + # This essentially finds the object (or multiple objects) with the given id, creates a new object + # from the attributes, and then calls destroy on it. + # + # ==== Parameters + # + # * +id+ - This should be the id or an array of ids to be destroyed. + # + # ==== Examples + # + # # Destroy a single object + # Todo.destroy(1) + # + # # Destroy multiple objects + # todos = [1,2,3] + # Todo.destroy(todos) + def destroy(id) + if id.is_a?(Array) + find(id).each(&:destroy) + else + find(id).destroy + end + end + + # Deletes the row with a primary key matching the +id+ argument, using a + # SQL +DELETE+ statement, and returns the number of rows deleted. Active + # Record objects are not instantiated, so the object's callbacks are not + # executed, including any <tt>:dependent</tt> association options. + # + # You can delete multiple rows at once by passing an Array of <tt>id</tt>s. + # + # Note: Although it is often much faster than the alternative, #destroy, + # skipping callbacks might bypass business logic in your application + # that ensures referential integrity or performs other essential jobs. + # + # ==== Examples + # + # # Delete a single row + # Todo.delete(1) + # + # # Delete multiple rows + # Todo.delete([2,3,4]) + def delete(id_or_array) + where(primary_key => id_or_array).delete_all + end + + def _insert_record(values) # :nodoc: + primary_key_value = nil + + if primary_key && Hash === values + arel_primary_key = arel_attribute(primary_key) + primary_key_value = values[arel_primary_key] + + if !primary_key_value && prefetch_primary_key? + primary_key_value = next_sequence_value + values[arel_primary_key] = primary_key_value + end + end + + if values.empty? + im = arel_table.compile_insert(connection.empty_insert_statement_value) + im.into arel_table + else + im = arel_table.compile_insert(_substitute_values(values)) + end + + connection.insert(im, "#{self} Create", primary_key || false, primary_key_value) + end + + def _update_record(values, id, id_was) # :nodoc: + bind = predicate_builder.build_bind_attribute(primary_key, id_was || id) + um = arel_table.where( + arel_attribute(primary_key).eq(bind) + ).compile_update(_substitute_values(values), primary_key) + + connection.update(um, "#{self} Update") + end + private # Called by +instantiate+ to decide which class to use for a new # record instance. @@ -80,6 +206,13 @@ module ActiveRecord def discriminate_class_for_record(record) self end + + def _substitute_values(values) + values.map do |attr, value| + bind = predicate_builder.build_bind_attribute(attr.name, value) + [attr, bind] + end + end end # Returns true if this object hasn't been saved yet -- that is, a record @@ -228,7 +361,7 @@ module ActiveRecord def becomes(klass) became = klass.new became.instance_variable_set("@attributes", @attributes) - became.instance_variable_set("@mutation_tracker", @mutation_tracker) if defined?(@mutation_tracker) + became.instance_variable_set("@mutations_from_database", @mutations_from_database) if defined?(@mutations_from_database) became.instance_variable_set("@changed_attributes", attributes_changed_by_setter) became.instance_variable_set("@new_record", new_record?) became.instance_variable_set("@destroyed", destroyed?) @@ -577,7 +710,7 @@ module ActiveRecord rows_affected = 0 @_trigger_update_callback = true else - rows_affected = self.class.unscoped._update_record attributes_values, id, id_in_database + rows_affected = self.class._update_record(attributes_values, id, id_in_database) @_trigger_update_callback = rows_affected > 0 end @@ -591,7 +724,7 @@ module ActiveRecord def _create_record(attribute_names = self.attribute_names) attributes_values = arel_attributes_with_values_for_create(attribute_names) - new_id = self.class.unscoped.insert attributes_values + new_id = self.class._insert_record(attributes_values) self.id ||= new_id if self.class.primary_key @new_record = false |