(This commit is for 10.3 and upper branches)
In case of a pattern of non-STMT_END-marked Rows-log-event (A) followed by
a STMT_END marked one (B) mysqlbinlog mixes up the base64 encoded rows events
with their pseudo sql representation produced by the verbose option:
BINLOG '
base64 encoded data for A
### verbose section for A
base64 encoded data for B
### verbose section for B
'/*!*/;
In effect the produced BINLOG '...' query is not valid and is rejected with the error.
Examples of this way malformed BINLOG could have been found in binlog_row_annotate.result
that gets corrected with the patch.
The issue is fixed with introduction an auxiliary IO_CACHE to hold on the verbose
comments until the terminal STMT_END event is found. The new cache is emptied
out after two pre-existing ones are done at that time.
The correctly produced output now for the above case is as the following:
BINLOG '
base64 encoded data for A
base64 encoded data for B
'/*!*/;
### verbose section for A
### verbose section for B
Thanks to Alexey Midenkov for the problem recognition and attempt to tackle,
and to Venkatesh Duggirala who produced a patch for the upstream whose
idea is exploited here, as well as to MDEV-23077 reporter LukeXwang who
also contributed a piece of a patch aiming at this issue.
Problem:
========
During point in time recovery of binary log syntax error is reported for
BEGIN statement and recovery fails.
Analysis:
=========
In MariaDB 10.3 and later, setting the sql_mode system variable to Oracle
allows the server to understand a subset of Oracle's PL/SQL language. When
sql_mode=ORACLE is set, it switches the parser from the MariaDB parser to
Oracle compatible parser. With this change 'BEGIN' is not considered as
'START TRANSACTION'. Hence the syntax error is reported.
Fix:
===
At preset 'BEGIN' query is generated from 'Gtid_log_event::print'. The current
session specific 'sql_mode' information is not present as part of
'Gtid_log_event'. If it was available then, mysqlbinlog tool can make use of
'sql_mode == ORACLE' and can output "START TRANSACTION" in this particular
mode and for other sql_modes it will write "BEGIN" as part of output. Since it
is not available 'mysqlbinlog' tool will output all 'BEGIN' statements as
'START TRANSACTION' irrespective of 'sql_mode'.
Analysis
Mysqlbinlog output for encrypted binary log
#Q> insert into tab1 values (3,'row 003')
#190912 17:36:35 server id 10221 end_log_pos 980 CRC32 0x53bcb3d3 Table_map: `test`.`tab1` mapped to number 19
# at 940
#190912 17:36:35 server id 10221 end_log_pos 1026 CRC32 0xf2ae5136 Write_rows: table id 19 flags: STMT_END_F
Here we can see Table_map_log_event ends at 980 but Next event starts at 940.
And the reason for that is we do not send START_ENCRYPTION_EVENT to the slave
Solution:-
Send Start_encryption_log_event as Ignorable_log_event to slave(mysqlbinlog),
So that mysqlbinlog can update its log_pos.
Since Slave can request multiple FORMAT_DESCRIPTION_EVENT while master does not
have so We only update slave master pos when master actually have the
FORMAT_DESCRIPTION_EVENT. Similar logic should be applied for START_ENCRYPTION_EVENT.
Also added the test case when new server reads the data from old server which
does not send START_ENCRYPTION_EVENT to slave.
Master Slave Upgrade Scenario.
When Slave is updated first, Slave will have extra logic of handling
START_ENCRYPTION_EVENT But master willnot be sending START_ENCRYPTION_EVENT.
So there will be no issue.
When Master is updated first, It will send START_ENCRYPTION_EVENT to
slave , But slave will ignore this event in queue_event.
This allows one to run the test suite even if any of the following
options are changed:
- character-set-server
- collation-server
- join-cache-level
- log-basename
- max-allowed-packet
- optimizer-switch
- query-cache-size and query-cache-type
- skip-name-resolve
- table-definition-cache
- table-open-cache
- Some innodb options
etc
Changes:
- Don't print out the value of system variables as one can't depend on
them to being constants.
- Don't set global variables to 'default' as the default may not
be the same as the test was started with if there was an additional
option file. Instead save original value and reset it at end of test.
- Test that depends on the latin1 character set should include
default_charset.inc or set the character set to latin1
- Test that depends on the original optimizer switch, should include
default_optimizer_switch.inc
- Test that depends on the value of a specific system variable should
set it in the test (like optimizer_use_condition_selectivity)
- Split subselect3.test into subselect3.test and subselect3.inc to
make it easier to set and reset system variables.
- Added .opt files for test that required specfic options that could
be changed by external configuration files.
- Fixed result files in rockdsb & tokudb that had not been updated for
a while.
Main problem was that no log-event print function checked for disk
full error on the IO_CACHE.
All changes in this patch only affects mysqlbinlog, not the server!
- Changed all log-event print functions to return 1 on error
- Fixed memory usage when not using --flashback.
- Added printing of number of rows in row events. Can be disabled with
--print-row-count=0
- Print annotated rows when using mysqlbinlog --short-form
- Fixed that mysqlbinlog --debug works
- Fixed create_drop_binlog.test test failure
- Reorganized fields in PRINT_EVENT_INFO to be according to size to
optimize storage
- Don't change print_row_event_position or print_row_counts if set by user
- Remove some testing of argument to my_free is 0
- base64-output=never is now supported and works in all context
- Updated help information for --base64-output and --short-form
- print_row_count is now on by default. Reset automatically if --short-form
is used
- Removed obsolote warning for mysql 5.6.0
- More DBUG_PRINT for mysqltest.cc
- my_b_write_byte() now checks for flush failures. This fixed a memory
overrun on disk full
- my_b_printf() now returns 1 on failure, 0 on ok. This simplifies code
and no old code was using the old return value of my_b_printf().
- my_b_Write_backtick_quote() now returns 1 on failure and 0 on ok
- Fixed some error conditions in log printing that was not previously
handled.
- Slave_rows_error_report() can now handle longlong positions
- Write_on_release_cache() rewritten so that we can detect errors
on flush. Not depending on automatic release anymore.
- Changed types for Pos and End_log_pos to 64 bit in SHOW BINLOG EVENTS
- Fixed that copy_event_cache_to_string_and_reinit() works with strings
longer than 4G (Changed to use LEX_STRING instead of String)
- Restricted binlog_rows_event_max_size to UINT32_MAX-1 as String's are
anyway restricted to UINT32_MAX
- Fixed bug in rpl_binlog_state::write_to_iocache() which hide write
failures (duplicate variable name)
- Fixed bug in String::append if original string was not allocated
- Stop mysqlbinlog output at once if there is an error.
- Before printing error message, flush result file. This ensures that
the error message is printed last. (Easier to find)
- created binlog_encryption test suite and added it to the default list
- moved some tests from rpl, binlog and multisource suites to extra
so that they could be re-used in different suites
- made minor changes in include files
