diff options
Diffstat (limited to 'activerecord/lib/active_record')
4 files changed, 43 insertions, 39 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 7bf548fcba..a918a8b035 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -1028,11 +1028,12 @@ module ActiveRecord end # Given a set of columns and an ORDER BY clause, returns the columns for a SELECT DISTINCT. - # Both PostgreSQL and Oracle overrides this for custom DISTINCT syntax - they + # PostgreSQL, MySQL, and Oracle overrides this for custom DISTINCT syntax - they # require the order columns appear in the SELECT. # # columns_for_distinct("posts.id", ["posts.created_at desc"]) - def columns_for_distinct(columns, orders) #:nodoc: + # + def columns_for_distinct(columns, orders) # :nodoc: columns end diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb index 37e4eb24a8..0615e646b1 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb @@ -623,6 +623,7 @@ module ActiveRecord # it can be helpful to provide these in a migration's +change+ method so it can be reverted. # In that case, +options+ and the block will be used by create_table. def drop_table(table_name, options = {}) + create_table_info_cache.delete(table_name) if create_table_info_cache.key?(table_name) execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}" end @@ -772,6 +773,21 @@ module ActiveRecord end end + # In MySQL 5.7.5 and up, ONLY_FULL_GROUP_BY affects handling of queries that use + # DISTINCT and ORDER BY. It requires the ORDER BY columns in the select list for + # distinct queries, and requires that the ORDER BY include the distinct column. + # See https://dev.mysql.com/doc/refman/5.7/en/group-by-handling.html + def columns_for_distinct(columns, orders) # :nodoc: + order_columns = orders.reject(&:blank?).map { |s| + # Convert Arel node to string + s = s.to_sql unless s.is_a?(String) + # Remove any ASC/DESC modifiers + s.gsub(/\s+(?:ASC|DESC)\b/i, '') + }.reject(&:blank?).map.with_index { |column, i| "#{column} AS alias_#{i}" } + + [super, *order_columns].join(', ') + end + def strict_mode? self.class.type_cast_config_to_boolean(@config.fetch(:strict, true)) end @@ -951,11 +967,13 @@ module ActiveRecord subsubselect = select.clone subsubselect.projections = [key] + # Materialize subquery by adding distinct + # to work with MySQL 5.7.6 which sets optimizer_switch='derived_merge=on' + subsubselect.distinct unless select.limit || select.offset || select.orders.any? + subselect = Arel::SelectManager.new(select.engine) subselect.project Arel.sql(key.name) - # Materialized subquery by adding distinct - # to work with MySQL 5.7.6 which sets optimizer_switch='derived_merge=on' - subselect.from subsubselect.distinct.as('__active_record_temp') + subselect.from subsubselect.as('__active_record_temp') end def mariadb? @@ -1018,9 +1036,12 @@ module ActiveRecord end end + def create_table_info_cache # :nodoc: + @create_table_info_cache ||= {} + end + def create_table_info(table_name) # :nodoc: - @create_table_info_cache = {} - @create_table_info_cache[table_name] ||= select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"] + create_table_info_cache[table_name] ||= select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"] end def create_table_definition(name, temporary = false, options = nil, as = nil) # :nodoc: diff --git a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb index f4686b680c..96a3a44b30 100644 --- a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb @@ -99,33 +99,15 @@ module ActiveRecord # DATABASE STATEMENTS ====================================== #++ - # FIXME: re-enable the following once a "better" query_cache solution is in core - # - # The overrides below perform much better than the originals in AbstractAdapter - # because we're able to take advantage of mysql2's lazy-loading capabilities - # - # # Returns a record hash with the column names as keys and column values - # # as values. - # def select_one(sql, name = nil) - # result = execute(sql, name) - # result.each(as: :hash) do |r| - # return r - # end - # end - # - # # Returns a single value from a record - # def select_value(sql, name = nil) - # result = execute(sql, name) - # if first = result.first - # first.first - # end - # end - # - # # Returns an array of the values of the first column in a select: - # # select_values("SELECT id FROM companies LIMIT 3") => [1,2,3] - # def select_values(sql, name = nil) - # execute(sql, name).map { |row| row.first } - # end + # Returns a record hash with the column names as keys and column values + # as values. + def select_one(arel, name = nil, binds = []) + arel, binds = binds_from_relation(arel, binds) + execute(to_sql(arel, binds), name).each(as: :hash) do |row| + @connection.next_result while @connection.more_results? + return row + end + end # Returns an array of arrays containing the field values. # Order is the same as that returned by +columns+. diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb index a1ec570042..e313a34c3a 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb @@ -390,12 +390,12 @@ module ActiveRecord "average" => "avg", } - protected + # Returns the version of the connected PostgreSQL server. + def postgresql_version + @connection.server_version + end - # Returns the version of the connected PostgreSQL server. - def postgresql_version - @connection.server_version - end + protected # See http://www.postgresql.org/docs/current/static/errcodes-appendix.html FOREIGN_KEY_VIOLATION = "23503" |