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  1. MariaDB Server
  2. MDEV-24402

CHECK TABLE may miss some cases of index inconsistencies

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    Description

      Looks as if some cases of InnoDB index inconsistencies – see e.g. MDEV-22373 – are missed by CHECK TABLE.

      InnoDB currently ignores any other CHECK TABLE attributes than QUICK (which will suppress the time-consuming checks of the upper levels of the index trees).

      Most importantly, InnoDB is ignoring the attribute EXTENDED, and is essentially only performing a MVCC COUNT(*) in each index. A verified case exists where the record counts in the indexes would match, yet the records do not match between the indexes. A true EXTENDED check should report any mismatch between the clustered index (primary key) and the secondary index records.

      Note: By the design of InnoDB MVCC (see MDEV-17598 for some discussion), secondary indexes may contain multiple copies of a record, while in the clustered index the multiple versions are formed via a singly-linked list that the undo log pages are part of.

      An extremely extended test would have to check that in any possible read view, the secondary indexes match the clustered index, instead of only checking the current read view.

      It may turn out that only a special ‘locking’ variant of CHECK TABLE would be able to detect truly any type of mismatch.

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          blocks

          Task - A task that needs to be done. MDEV-28349 Provide "crash safe" options for CHECK TABLE and ALTER TABLE ... CHECK PARTITION ...

          • Major - Major loss of function.
          • Open
          causes

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29886 Assertion `!index->table->is_temporary()' failed in trx_undo_prev_version_build upon CHECK

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29978 Corruption errors upon CHECK on temporary InnoDB table

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-35227 Executing CHECK TABLE...EXTENDED right after server startup may attempt to access too old history

          • Major - Major loss of function.
          • Confirmed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-25459 MVCC read from index on CHAR or VARCHAR wrongly omits rows

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29593 Purge misses a chance to free not-yet-reused undo pages

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29666 InnoDB fails to purge secondary index records when indexed virtual columns exist

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29823 Secondary index records may never be purged after rollback

          • Major - Major loss of function.
          • Confirmed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-9663 InnoDB assertion failure: *cursor->index->name == TEMP_INDEX_PREFIX, or !cursor->index->is_committed()

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-11802 innodb.innodb_bug14676111 fails in buildbot due to InnoDB purge failing to start when there is work to do

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-22373 Unable to find a record to delete-mark ends up crashing mysqld process after upgrading from 10.1.43 to 10.4

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-29954 Unique hash key on column prefix is computed incorrectly

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-30129 MySQL 5.7 --> MariaDB 10.8 switch: mysqlcheck --check --extended hangs on table

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Closed

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              marko Marko Mäkelä
              hholzgra Hartmut Holzgraefe
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                Updated:
                Resolved:

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