diff options
Diffstat (limited to 'activerecord/lib/active_record/relation.rb')
| -rw-r--r-- | activerecord/lib/active_record/relation.rb | 203 |
1 files changed, 111 insertions, 92 deletions
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb index 9857ab0f8f..d92ff781ee 100644 --- a/activerecord/lib/active_record/relation.rb +++ b/activerecord/lib/active_record/relation.rb @@ -1,4 +1,5 @@ # -*- coding: utf-8 -*- +require 'arel/collectors/bind' module ActiveRecord # = Active Record Relation @@ -7,27 +8,26 @@ module ActiveRecord MULTI_VALUE_METHODS = [:includes, :eager_load, :preload, :select, :group, :order, :joins, :where, :having, :bind, :references, - :extending] + :extending, :unscope] SINGLE_VALUE_METHODS = [:limit, :offset, :lock, :readonly, :from, :reordering, :reverse_order, :distinct, :create_with, :uniq] + INVALID_METHODS_FOR_DELETE_ALL = [:limit, :distinct, :offset, :group, :having] VALUE_METHODS = MULTI_VALUE_METHODS + SINGLE_VALUE_METHODS include FinderMethods, Calculations, SpawnMethods, QueryMethods, Batches, Explain, Delegation attr_reader :table, :klass, :loaded - attr_accessor :default_scoped alias :model :klass alias :loaded? :loaded - alias :default_scoped? :default_scoped def initialize(klass, table, values = {}) - @klass = klass - @table = table - @values = values - @loaded = false - @default_scoped = false + @klass = klass + @table = table + @values = values + @offsets = {} + @loaded = false end def initialize_copy(other) @@ -72,9 +72,9 @@ module ActiveRecord binds) end - def update_record(values, id, id_was) # :nodoc: + def _update_record(values, id, id_was) # :nodoc: substitutes, binds = substitute_values values - um = @klass.unscoped.where(@klass.arel_table[@klass.primary_key].eq(id_was || id)).arel.compile_update(substitutes) + um = @klass.unscoped.where(@klass.arel_table[@klass.primary_key].eq(id_was || id)).arel.compile_update(substitutes, @klass.primary_key) @klass.connection.update( um, @@ -154,34 +154,58 @@ module ActiveRecord first || new(attributes, &block) end - # Finds the first record with the given attributes, or creates a record with the attributes - # if one is not found. + # Finds the first record with the given attributes, or creates a record + # with the attributes if one is not found: # - # ==== Examples - # # Find the first user named Penélope or create a new one. + # # Find the first user named "Penélope" or create a new one. # User.find_or_create_by(first_name: 'Penélope') - # # => <User id: 1, first_name: 'Penélope', last_name: nil> + # # => #<User id: 1, first_name: "Penélope", last_name: nil> # - # # Find the first user named Penélope or create a new one. + # # Find the first user named "Penélope" or create a new one. # # We already have one so the existing record will be returned. # User.find_or_create_by(first_name: 'Penélope') - # # => <User id: 1, first_name: 'Penélope', last_name: nil> + # # => #<User id: 1, first_name: "Penélope", last_name: nil> # - # # Find the first user named Scarlett or create a new one with a particular last name. + # # Find the first user named "Scarlett" or create a new one with + # # a particular last name. # User.create_with(last_name: 'Johansson').find_or_create_by(first_name: 'Scarlett') - # # => <User id: 2, first_name: 'Scarlett', last_name: 'Johansson'> + # # => #<User id: 2, first_name: "Scarlett", last_name: "Johansson"> # - # # Find the first user named Scarlett or create a new one with a different last name. - # # We already have one so the existing record will be returned. + # This method accepts a block, which is passed down to +create+. The last example + # above can be alternatively written this way: + # + # # Find the first user named "Scarlett" or create a new one with a + # # different last name. # User.find_or_create_by(first_name: 'Scarlett') do |user| - # user.last_name = "O'Hara" + # user.last_name = 'Johansson' # end - # # => <User id: 2, first_name: 'Scarlett', last_name: 'Johansson'> + # # => #<User id: 2, first_name: "Scarlett", last_name: "Johansson"> + # + # This method always returns a record, but if creation was attempted and + # failed due to validation errors it won't be persisted, you get what + # +create+ returns in such situation. + # + # Please note *this method is not atomic*, it runs first a SELECT, and if + # there are no results an INSERT is attempted. If there are other threads + # or processes there is a race condition between both calls and it could + # be the case that you end up with two similar records. + # + # Whether that is a problem or not depends on the logic of the + # application, but in the particular case in which rows have a UNIQUE + # constraint an exception may be raised, just retry: + # + # begin + # CreditAccount.find_or_create_by(user_id: user.id) + # rescue ActiveRecord::RecordNotUnique + # retry + # end + # def find_or_create_by(attributes, &block) find_by(attributes) || create(attributes, &block) end - # Like <tt>find_or_create_by</tt>, but calls <tt>create!</tt> so an exception is raised if the created record is invalid. + # Like <tt>find_or_create_by</tt>, but calls <tt>create!</tt> so an exception + # is raised if the created record is invalid. def find_or_create_by!(attributes, &block) find_by(attributes) || create!(attributes, &block) end @@ -201,6 +225,7 @@ module ActiveRecord # Please see further details in the # {Active Record Query Interface guide}[http://guides.rubyonrails.org/active_record_querying.html#running-explain]. def explain + #TODO: Fix for binds. exec_explain(collecting_queries_for_explain { exec_queries }) end @@ -216,15 +241,19 @@ module ActiveRecord # Returns size of the records. def size - loaded? ? @records.length : count + loaded? ? @records.length : count(:all) end # Returns true if there are no records. def empty? return @records.empty? if loaded? - c = count - c.respond_to?(:zero?) ? c.zero? : c.empty? + if limit_value == 0 + true + else + c = count(:all) + c.respond_to?(:zero?) ? c.zero? : c.empty? + end end # Returns true if there are any records. @@ -289,7 +318,7 @@ module ActiveRecord stmt.table(table) stmt.key = table[primary_key] - if with_default_scope.joins_values.any? + if joins_values.any? @klass.connection.join_to_update(stmt, arel) else stmt.take(arel.limit) @@ -297,7 +326,8 @@ module ActiveRecord stmt.wheres = arel.constraints end - @klass.connection.update stmt, 'SQL', bind_values + bvs = bind_values + arel.bind_values + @klass.connection.update stmt, 'SQL', bvs end # Updates an object (or multiple objects) and saves it to the database, if validations pass. @@ -401,12 +431,21 @@ module ActiveRecord # If you need to destroy dependent associations or call your <tt>before_*</tt> or # +after_destroy+ callbacks, use the +destroy_all+ method instead. # - # If a limit scope is supplied, +delete_all+ raises an ActiveRecord error: + # If an invalid method is supplied, +delete_all+ raises an ActiveRecord error: # # Post.limit(100).delete_all - # # => ActiveRecord::ActiveRecordError: delete_all doesn't support limit scope + # # => ActiveRecord::ActiveRecordError: delete_all doesn't support limit def delete_all(conditions = nil) - raise ActiveRecordError.new("delete_all doesn't support limit scope") if self.limit_value + invalid_methods = INVALID_METHODS_FOR_DELETE_ALL.select { |method| + if MULTI_VALUE_METHODS.include?(method) + send("#{method}_values").any? + else + send("#{method}_value") + end + } + if invalid_methods.any? + raise ActiveRecordError.new("delete_all doesn't support #{invalid_methods.join(', ')}") + end if conditions where(conditions).delete_all @@ -414,7 +453,7 @@ module ActiveRecord stmt = Arel::DeleteManager.new(arel.engine) stmt.from(table) - if with_default_scope.joins_values.any? + if joins_values.any? @klass.connection.join_to_delete(stmt, arel, table[primary_key]) else stmt.wheres = arel.constraints @@ -469,9 +508,10 @@ module ActiveRecord end def reset - @first = @last = @to_sql = @order_clause = @scope_for_create = @arel = @loaded = nil + @last = @to_sql = @order_clause = @scope_for_create = @arel = @loaded = nil @should_eager_load = @join_dependency = nil @records = [] + @offsets = {} self end @@ -480,25 +520,43 @@ module ActiveRecord # User.where(name: 'Oscar').to_sql # # => SELECT "users".* FROM "users" WHERE "users"."name" = 'Oscar' def to_sql - @to_sql ||= klass.connection.to_sql(arel, bind_values.dup) + @to_sql ||= begin + relation = self + connection = klass.connection + visitor = connection.visitor + + if eager_loading? + find_with_associations { |rel| relation = rel } + end + + arel = relation.arel + binds = (arel.bind_values + relation.bind_values).dup + binds.map! { |bv| connection.quote(*bv.reverse) } + collect = visitor.accept(arel.ast, Arel::Collectors::Bind.new) + collect.substitute_binds(binds).join + end end # Returns a hash of where conditions. # # User.where(name: 'Oscar').where_values_hash # # => {name: "Oscar"} - def where_values_hash - scope = with_default_scope - equalities = scope.where_values.grep(Arel::Nodes::Equality).find_all { |node| - node.left.relation.name == table_name + def where_values_hash(relation_table_name = table_name) + equalities = where_values.grep(Arel::Nodes::Equality).find_all { |node| + node.left.relation.name == relation_table_name } - binds = Hash[scope.bind_values.find_all(&:first).map { |column, v| [column.name, v] }] - binds.merge!(Hash[bind_values.find_all(&:first).map { |column, v| [column.name, v] }]) + binds = Hash[bind_values.find_all(&:first).map { |column, v| [column.name, v] }] Hash[equalities.map { |where| name = where.left.name - [name, binds.fetch(name.to_s) { where.right }] + [name, binds.fetch(name.to_s) { + case where.right + when Array then where.right.map(&:val) + else + where.right.val + end + }] }] end @@ -530,6 +588,8 @@ module ActiveRecord # Compares two relations for equality. def ==(other) case other + when Associations::CollectionProxy, AssociationRelation + self == other.to_a when Relation other.to_sql == to_sql when Array @@ -541,16 +601,6 @@ module ActiveRecord q.pp(self.to_a) end - def with_default_scope #:nodoc: - if default_scoped? && default_scope = klass.send(:build_default_scope) - default_scope = default_scope.merge(self) - default_scope.default_scoped = false - default_scope - else - self - end - end - # Returns true if relation is blank. def blank? to_a.blank? @@ -570,22 +620,17 @@ module ActiveRecord private def exec_queries - default_scoped = with_default_scope + @records = eager_loading? ? find_with_associations : @klass.find_by_sql(arel, arel.bind_values + bind_values) - if default_scoped.equal?(self) - @records = eager_loading? ? find_with_associations : @klass.find_by_sql(arel, bind_values) - - preload = preload_values - preload += includes_values unless eager_loading? - preload.each do |associations| - ActiveRecord::Associations::Preloader.new(@records, associations).run - end - - @records.each { |record| record.readonly! } if readonly_value - else - @records = default_scoped.to_a + preload = preload_values + preload += includes_values unless eager_loading? + preloader = ActiveRecord::Associations::Preloader.new + preload.each do |associations| + preloader.preload @records, associations end + @records.each { |record| record.readonly! } if readonly_value + @loaded = true @records end @@ -603,34 +648,8 @@ module ActiveRecord # always convert table names to downcase as in Oracle quoted table names are in uppercase joined_tables = joined_tables.flatten.compact.map { |t| t.downcase }.uniq - string_tables = tables_in_string(to_sql) - if (references_values - joined_tables).any? - true - elsif !ActiveRecord::Base.disable_implicit_join_references && - (string_tables - joined_tables).any? - ActiveSupport::Deprecation.warn( - "It looks like you are eager loading table(s) (one of: #{string_tables.join(', ')}) " \ - "that are referenced in a string SQL snippet. For example: \n" \ - "\n" \ - " Post.includes(:comments).where(\"comments.title = 'foo'\")\n" \ - "\n" \ - "Currently, Active Record recognizes the table in the string, and knows to JOIN the " \ - "comments table to the query, rather than loading comments in a separate query. " \ - "However, doing this without writing a full-blown SQL parser is inherently flawed. " \ - "Since we don't want to write an SQL parser, we are removing this functionality. " \ - "From now on, you must explicitly tell Active Record when you are referencing a table " \ - "from a string:\n" \ - "\n" \ - " Post.includes(:comments).where(\"comments.title = 'foo'\").references(:comments)\n" \ - "\n" \ - "If you don't rely on implicit join references you can disable the feature entirely " \ - "by setting `config.active_record.disable_implicit_join_references = true`." - ) - true - else - false - end + (references_values - joined_tables).any? end def tables_in_string(string) |