diff options
Diffstat (limited to 'storage/innobase/row/row0umod.cc')
| -rw-r--r-- | storage/innobase/row/row0umod.cc | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/storage/innobase/row/row0umod.cc b/storage/innobase/row/row0umod.cc index 0b1d800212f..c614f75d005 100644 --- a/storage/innobase/row/row0umod.cc +++ b/storage/innobase/row/row0umod.cc @@ -1192,7 +1192,16 @@ close_table: if (!row_undo_search_clust_to_pcur(node)) { /* As long as this rolling-back transaction exists, the PRIMARY KEY value pointed to by the undo log - record must exist. But, it is possible that the record + record should exist. + + However, if InnoDB is killed during a rollback, or + shut down during the rollback of recovered + transactions, then after restart we may try to roll + back some of the same undo log records again, because + trx_roll_try_truncate() is not being invoked after + every undo log record. + + It is also possible that the record was not modified yet (the DB_ROLL_PTR does not match node->roll_ptr) and thus there is nothing to roll back. @@ -1200,8 +1209,11 @@ close_table: record after successfully acquiring an exclusive lock on the the clustered index record. That lock will not be released before the transaction is committed or - fully rolled back. */ - ut_ad(node->pcur.btr_cur.low_match == node->ref->n_fields); + fully rolled back. (Exception: if the server was + killed, restarted, and shut down again before the + rollback of the recovered transaction was completed, + it is possible that the transaction was partially + rolled back and locks released.) */ goto close_table; } |