Commit a923d6f49c disabled numeric setting
of character_set_* variables with non-default values:
MariaDB [(none)]> set character_set_client=224;
ERROR 1115 (42000): Unknown character set: '224'
However the corresponding binlog functionality still write numeric
values for log event, and this will break binlog replay if the value is
not default. Now make the server use 'String' type for
'character_set_client' when generating binlog events
Before:
/*!\C utf8mb4 *//*!*/;
SET @@session.character_set_client=224,@@session.collation_connection=224,@@session.collation_server=33/*!*/;
After:
/*!\C utf8mb4 *//*!*/;
SET @@session.character_set_client=utf8mb4,@@session.collation_connection=33,@@session.collation_server=8/*!*/;
Note: prior to the previous commit, setting with '224' or '45' or
'utf8mb4' have the same effect, as they all set the parameter to
'utf8mb4'.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.
- Major rewrite of ddl_log.cc and ddl_log.h
- ddl_log.cc described in the beginning how the recovery works.
- ddl_log.log has unique signature and is dynamic. It's easy to
add more information to the header and other ddl blocks while still
being able to execute old ddl entries.
- IO_SIZE for ddl blocks is now dynamic. Can be changed without affecting
recovery of old logs.
- Code is more modular and is now usable outside of partition handling.
- Renamed log file to dll_recovery.log and added option --log-ddl-recovery
to allow one to specify the path & filename.
- Added ddl_log_entry_phase[], number of phases for each DDL action,
which allowed me to greatly simply set_global_from_ddl_log_entry()
- Changed how strings are stored in log entries, which allows us to
store much more information in a log entry.
- ddl log is now always created at start and deleted on normal shutdown.
This simplices things notable.
- Added probes debug_crash_here() and debug_simulate_error() to simply
crash testing and allow crash after a given number of times a probe
is executed. See comments in debug_sync.cc and rename_table.test for
how this can be used.
- Reverting failed table and view renames is done trough the ddl log.
This ensures that the ddl log is tested also outside of recovery.
- Added helper function 'handler::needs_lower_case_filenames()'
- Extend binary log with Q_XID events. ddl log handling is using this
to check if a ddl log entry was logged to the binary log (if yes,
it will be deleted from the log during ddl_log_close_binlogged_events()
- If a DDL entry fails 3 time, disable it. This is to ensure that if
we have a crash in ddl recovery code the server will not get stuck
in a forever crash-restart-crash loop.
mysqltest.cc changes:
- --die will now replace $variables with their values
- $error will contain the error of the last failed statement
storage engine changes:
- maria_rename() was changed to be more robust against crashes during
rename.
