Under unknown circumstances, the SQL layer may wrongly disregard an
invocation of thd_mark_transaction_to_rollback() when an InnoDB
transaction had been aborted (rolled back) due to one of the following errors:
* HA_ERR_LOCK_DEADLOCK
* HA_ERR_RECORD_CHANGED (if innodb_snapshot_isolation=ON)
* HA_ERR_LOCK_WAIT_TIMEOUT (if innodb_rollback_on_timeout=ON)
Such an error used to cause a crash of InnoDB during transaction commit.
These changes aim to catch and report the error earlier, so that not only
this crash can be avoided but also the original root cause be found and
fixed more easily later.
The idea of this fix is from Michael 'Monty' Widenius.
HA_ERR_ROLLBACK: A new error code that will be translated into
ER_ROLLBACK_ONLY, signalling that the current transaction
has been aborted and the only allowed action is ROLLBACK.
trx_t::state: Add TRX_STATE_ABORTED that is like
TRX_STATE_NOT_STARTED, but noting that the transaction had been
rolled back and aborted.
trx_t::is_started(): Replaces trx_is_started().
ha_innobase: Check the transaction state in various places.
Simplify the logic around SAVEPOINT.
ha_innobase::is_valid_trx(): Replaces ha_innobase::is_read_only().
The InnoDB logic around transaction savepoints, commit, and rollback
was unnecessarily complex and might have contributed to this
inconsistency. So, we are simplifying that logic as well.
trx_savept_t: Replace with const undo_no_t*. When we rollback to
a savepoint, all we need to know is the number of undo log records
that must survive.
trx_named_savept_t, DB_NO_SAVEPOINT: Remove. We can store undo_no_t
directly in the space allocated at innobase_hton->savepoint_offset.
fts_trx_create(): Do not copy previous savepoints.
fts_savepoint_rollback(): If a savepoint was not found, roll back
everything after the default savepoint of fts_trx_create().
The test innodb_fts.savepoint is extended to cover this code.
Reviewed by: Vladislav Lesin
Tested by: Matthias Leich
The issue is that record_should_be_deleted() returns true in
mysql_delete() even if sub-select with join gets error from storage
engine when DELETE FROM ... WHERE ... IN (SELECT ...) statement is
executed.
The same is true for mysql_update() where select->skip_record() returns
true even if sub-select with join gets error from storage engine.
In the test case if sub-select is chosen as deadlock victim the whole
transaction is rolled back during sub-select execution, but
mysql_delete()/mysql_update() continues transaction execution and invokes
table->delete_row() as record_should_be_deleted() wrongly returns true
in mysql_delete() and table->update_row() as select->skip_record(thd)
wrongly returns 1 for mysql_update().
record_should_be_deleted() wrogly returns true because thd->is_error()
returns false SQL_SELECT::skip_record() invoked from
record_should_be_deleted().
It's supposed that THD error should be set in rr_handle_error() called
from rr_sequential() during sub-select JOIN::exec_inner() execution.
But rr_handle_error() does not set THD error because
READ_RECORD::print_error is not set in JOIN_TAB::read_record.
READ_RECORD::print_error should be initialized in
init_read_record()/init_read_record_idx(). But make_join_readinfo() does
not invoke init_read_record()/init_read_record_idx() for
JOIN_TAB::read_record.
The fix is to set JOIN_TAB::read_record.print_error in
make_join_readinfo(), i.e. in the same place where
JOIN_TAB::read_record.table is set.
Reviewed by Sergey Petrunya.