diff options
Diffstat (limited to 'activerecord/lib/active_record')
3 files changed, 32 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb index 47dbf5a5f3..6924bb7e6f 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb @@ -51,6 +51,13 @@ module ActiveRecord true end + # Does this adapter support DDL rollbacks in transactions? That is, would + # CREATE TABLE or ALTER TABLE get rolled back by a transaction? PostgreSQL, + # SQL Server, and others support this. MySQL and others do not. + def supports_ddl_transactions? + false + end + # Should primary key values be selected from their corresponding # sequence before the insert statement? If true, next_sequence_value # is called before each insert to set the record's primary key. diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb index 723e1a42dd..bc6fd4e722 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb @@ -335,6 +335,10 @@ module ActiveRecord postgresql_version >= 80200 end + def supports_ddl_transactions? + true + end + # Returns the configured supported identifier length supported by PostgreSQL, # or report the default of 63 on PostgreSQL 7.x. def table_alias_length diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb index fd77f27b77..c7bc76264d 100644 --- a/activerecord/lib/active_record/migration.rb +++ b/activerecord/lib/active_record/migration.rb @@ -461,14 +461,22 @@ module ActiveRecord Base.logger.info "Migrating to #{migration.name} (#{migration.version})" # On our way up, we skip migrating the ones we've already migrated - # On our way down, we skip reverting the ones we've never migrated next if up? && migrated.include?(migration.version.to_i) + # On our way down, we skip reverting the ones we've never migrated if down? && !migrated.include?(migration.version.to_i) migration.announce 'never migrated, skipping'; migration.write - else - migration.migrate(@direction) - record_version_state_after_migrating(migration.version) + next + end + + begin + ddl_transaction do + migration.migrate(@direction) + record_version_state_after_migrating(migration.version) + end + rescue => e + canceled_msg = Base.connection.supports_ddl_transactions? ? "this and " : "" + raise StandardError, "An error has occurred, #{canceled_msg}all later migrations canceled:\n\n#{e}", e.backtrace end end end @@ -531,5 +539,14 @@ module ActiveRecord def down? @direction == :down end + + # Wrap the migration in a transaction only if supported by the adapter. + def ddl_transaction(&block) + if Base.connection.supports_ddl_transactions? + Base.transaction { block.call } + else + block.call + end + end end end |