mariadb/storage/maria/ma_recovery.h
unknown 1bc5e3b971 WL#3072 - Maria recovery
maria_read_log used to always print a warning message at startup
to say it is unsafe if ALTER TABLE was used. Now it prints it only
if the log does show the problem (=ALTER TABLE or CREATE SELECT, which
both disable logging of REDO_INSERT*).
For that, when ha_maria::external_lock() disables transactionality
it writes a LOGREC_INCOMPLETE_LOG to the log, which "maria_read_log -a"
picks up to write a warning.
REPAIR TABLE also disables those REDO_INSERT* but as maria_read_log
executes LOGREC_REDO_REPAIR no warning is needed.


storage/maria/ha_maria.cc:
  as we now log a record when disabling transactionility, we need the
  TRN to be set up first
storage/maria/ma_blockrec.c:
  comment
storage/maria/ma_loghandler.c:
  new type of log record
storage/maria/ma_loghandler.h:
  new type of log record
storage/maria/ma_recovery.c:
  * maria_apply_log() now returns a count of warnings. What currently
  produces warnings is:
  - skipping applying UNDOs though there are some (=> inconsistent table)
  - replaying log (in maria_read_log) though the log contains some
  ALTER TABLE or CREATE SELECT (log misses REDO_INSERT* for those
  and is so incomplete).
  Count of warnings affects the final message of maria_read_log and
  recovery (though in recovery none of the two conditions above should
  happen).
  * maria_read_log used to always print a warning message at startup
  to say it is unsafe if ALTER TABLE was used. Now it prints it only
  if the log does show the problem, i.e. ALTER TABLE or CREATE SELECT
  was used (both disable logging of REDO_INSERT* as those records are
  not needed for recovery; those missing records in turn make
  recreation-from-scratch, via maria_read_log, impossible). For that,
  when ha_maria::external_lock() disables transactionality,
  _ma_tmp_disable_logging_for_table() writes a LOGREC_INCOMPLETE_LOG to
  the log, which maria_apply_log() picks up to write a warning.
storage/maria/ma_recovery.h:
  maria_apply_log() returns a count of warnings
storage/maria/maria_def.h:
  _ma_tmp_disable_logging_for_table() grows so becomes a function
storage/maria/maria_read_log.c:
  maria_apply_log can now return a count of warnings, to temper the
  "SUCCESS" message printed in the end by maria_read_log.
  Advise users to make a backup first.
2007-11-14 12:51:16 +01:00

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C

/* Copyright (C) 2006,2007 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
WL#3072 Maria recovery
First version written by Guilhem Bichot on 2006-04-27.
Does not compile yet.
*/
/* This is the interface of this module. */
/* Performs recovery of the engine at start */
C_MODE_START
enum maria_apply_log_way
{ MARIA_LOG_APPLY, MARIA_LOG_DISPLAY_HEADER, MARIA_LOG_CHECK };
int maria_recover(void);
int maria_apply_log(LSN lsn, enum maria_apply_log_way apply,
FILE *trace_file,
my_bool execute_undo_phase, my_bool skip_DDLs,
my_bool take_checkpoints, uint *warnings_count);
C_MODE_END