Let
- T be a transactional table and N non-transactional table.
- B be begin, C commit and R rollback.
- N be a statement that accesses and changes only N-tables.
- T be a statement that accesses and changes only T-tables.
In RBR, changes to N-tables that happen early in a transaction are not immediately flushed
upon committing a statement. This behavior may, however, break consistency in the presence
of concurrency since changes done to N-tables become immediately visible to other
connections. To fix this problem, we do the following:
. B N N T C would log - B N C B N C B T C.
. B N N T R would log - B N C B N C B T R.
Note that we are not preserving history from the master as we are introducing a commit that
never happened. However, this seems to be more acceptable than the possibility of breaking
consistency in the presence of concurrency.
The problem is that there is only one autoinc value associated with
the query when binlogging. If more than one autoinc values are used
in the query, the autoinc values after the first one can be inserted
wrongly on slave. So these autoinc values can become inconsistent on
master and slave.
The problem is resolved by marking all the statements that invoke
a trigger or call a function that updated autoinc fields as unsafe,
and will switch to row-format in Mixed mode. Actually, the statement
is safe if just one autoinc value is used in sub-statement, but it's
impossible to check how many autoinc values are used in sub-statement.)
mysql-test/suite/rpl/r/rpl_auto_increment_update_failure.result:
Test result for bug#45677
mysql-test/suite/rpl/t/rpl_auto_increment_update_failure.test:
Added test to verify the following two properties:
P1) insert/update in an autoinc column causes statement to
be logged in row format if binlog_format=mixed
P2) if binlog_format=mixed, and a trigger or function contains
two or more inserts/updates in a table that has an autoinc
column, then the slave should not go out of sync, even if
there are concurrent transactions.
sql/sql_base.cc:
Added function 'has_write_table_with_auto_increment' to check
if one (or more) write tables have auto_increment columns.
Removed function 'has_two_write_locked_tables_with_auto_increment',
because the function is included in function
'has_write_table_with_auto_increment'.
"load data" statements were written to the binlog as a mix of the original statement
and bits recreated from parse-info. This relied on implementation details and broke
with IGNORE_SPACES and versioned comments.
We now completely resynthesize the query for LOAD DATA for binlog (which among other
things normalizes them somewhat with regard to case, spaces, etc.).
We have already parsed the query properly, so we make use of that rather
than mix-and-match string literals and parsed items.
This should make us safe with regard to versioned comments, even those
spanning multiple tokens. Also no longer affected by IGNORE_SPACES.
mysql-test/r/mysqlbinlog.result:
LOAD DATA INFILE normalized
mysql-test/suite/binlog/r/binlog_killed_simulate.result:
LOAD DATA INFILE normalized
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
LOAD DATA INFILE normalized
mysql-test/suite/binlog/r/binlog_stm_blackhole.result:
LOAD DATA INFILE normalized
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
LOAD DATA INFILE normalized
mysql-test/suite/rpl/r/rpl_innodb_mixed_dml.result:
LOAD DATA INFILE normalized
mysql-test/suite/rpl/r/rpl_loaddata.result:
LOAD DATA INFILE normalized
mysql-test/suite/rpl/r/rpl_loaddata_fatal.result:
LOAD DATA INFILE normalized; offsets adjusted to reflect that
mysql-test/suite/rpl/r/rpl_loaddata_map.result:
LOAD DATA INFILE normalized
mysql-test/suite/rpl/r/rpl_loaddatalocal.result:
test for #43746 - trying to break LOAD DATA part of parser
mysql-test/suite/rpl/r/rpl_stm_log.result:
LOAD DATA INFILE normalized
mysql-test/suite/rpl/t/rpl_loaddatalocal.test:
try to break the LOAD DATA part of the parser (test for #43746)
mysql-test/t/mysqlbinlog.test:
LOAD DATA INFILE normalized; adjust offsets to reflect that
sql/log_event.cc:
clean up Load_log_event::print_query and friends so they don't print
excess spaces. add support for printing charset names to print_query.
sql/log_event.h:
We already have three places where we synthesize LOAD DATA queries.
Better use one of those!
sql/sql_lex.h:
When binlogging LOAD DATA statements, we make up the statement to
be logged (from the parse-info, rather than substrings of the
original query) now. Consequently, we no longer need (string-)
pointers into the original query.
sql/sql_load.cc:
Completely rewrote write_execute_load_query_log_event() to synthesize the
LOAD DATA statement wholesale, rather than piece it together from
synthesized bits and literal excerpts from the original query. This
will not only give us a nice, normalized statement (all uppercase,
no excess spaces, etc.), it will also handle comments, including
versioned comments right, which is certainly more than we can say
about the previous incarnation.
sql/sql_yacc.yy:
We're no longer assembling LOAD DATA statements from bodyparts of the
original query, so some bookkeeping in the parser can go.
All statements executed by mysql_upgrade are binlogged and then are replicated to slave.
This will result in some errors. The report of this bug has demonstrated some examples.
Master and slave should be upgraded separately. All statements executed by
mysql_upgrade will not be binlogged.
--write-binlog and --skip-write-binlog options are added into mysql_upgrade.
These options control whether sql statements are binlogged or not.
HA_ERR_WRONG_INDEX
In RBR, disabling keys on slave table will break replication when
updating or deleting a record. When the slave thread tries to
find the row, by searching in the storage engine, it checks
whether the table has a key or not. If it has one, then the slave
thread uses it to search the record.
Nonetheless, the slave only checks whether the key exists or not,
it does not verify if it is active. Should the key be
disabled (eg, DBA has issued an ALTER TABLE ... DISABLE KEYS)
then it will result in error: HA_ERR_WRONG_INDEX.
This patch addresses this issue by making the slave thread also
check whether the key is active or not before actually using it.
Network error happened here, but it can be caused by CR_CONNECTION_ERROR,
CR_CONN_HOST_ERROR, CR_SERVER_GONE_ERROR, CR_SERVER_LOST, ER_CON_COUNT_ERROR,
and ER_SERVER_SHUTDOWN. We just check CR_SERVER_LOST here, so the test fails.
To fix the problem, check all errors that can be cause by the master shutdown.
mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test:
Added a 'if' sentence to check all errors that can be cause by the master shutdown.
mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result:
Test result is updated duo to the patch of bug#46931
But there is no Last_IO_Error reported.
On the master, if a binary log event is larger than max_allowed_packet,
ER_MASTER_FATAL_ERROR_READING_BINLOG and the specific reason of this error is
sent to a slave when it requests a dump from the master, thus leading
the I/O thread to stop.
On a slave, the I/O thread stops when receiving a packet larger than max_allowed_packet.
In both cases, however, there was no Last_IO_Error reported.
This patch adds code to report the Last_IO_Error and exact reason before stopping the
I/O thread and also reports the case the out memory pops up while
handling packets from the master.
sql/sql_repl.cc:
The master send the Specific reasons instead of "error reading log entry" to the slave which is requesting a dump.
if an fatal error is returned by read_log_event function.
In RBR, There is an inconsistency between slaves and master.
When INSERT statement which includes an auto_increment field is executed,
Store engine of master will check the value of the auto_increment field.
It will generate a sequence number and then replace the value, if its value is NULL or empty.
if the field's value is 0, the store engine will do like encountering the NULL values
unless NO_AUTO_VALUE_ON_ZERO is set into SQL_MODE.
In contrast, if the field's value is 0, Store engine of slave always generates a new sequence number
whether or not NO_AUTO_VALUE_ON_ZERO is set into SQL_MODE.
SQL MODE of slave sql thread is always consistency with master's.
Another variable is related to this bug.
If generateing a sequence number is decided by the values of
table->auto_increment_field_not_null and SQL_MODE(if includes MODE_NO_AUTO_VALUE_ON_ZERO)
The table->auto_increment_is_not_null is FALSE, which causes this bug to appear. ..
Essentially, Bug#45574 results in this bug. The 'CREATE DATABASE IF NOT EXISTS' statement was not
binlogged, when the database has existed.
Sometimes, the master and slaves become inconsistent. The "CREATE DATABASE
IF NOT EXISTS mysqltest1" statement is not binlogged
if the db 'mysqltest1' existed before the test case is executed.
So the db 'mysqltest1' can't be created on slave.
Patch of Bug#45574 has resolved this problem.
But I think it is better to replace 'mysqltest1' by default db 'test'.
If an EVENT is created without the DEFINER clause set explicitly or with it set
to CURRENT_USER, the master and slaves become inconsistent. This issue stems from
the fact that in both cases, the DEFINER is set to the CURRENT_USER of the current
thread. On the master, the CURRENT_USER is the mysqld's user, while on the slave,
the CURRENT_USER is empty for the SQL Thread which is responsible for executing
the statement.
To fix the problem, we do what follows. If the definer is not set explicitly,
a DEFINER clause is added when writing the query into binlog; if 'CURRENT_USER' is
used as the DEFINER, it is replaced with the value of the current user before
writing to binlog.
mysql-test/suite/rpl/r/rpl_create_if_not_exists.result:
Updated the result file after fixing bug#44331
mysql-test/suite/rpl/r/rpl_drop_if_exists.result:
Updated the result file after fixing bug#44331
mysql-test/suite/rpl/r/rpl_events.result:
Test result of Bug#44331
mysql-test/suite/rpl/r/rpl_innodb_mixed_dml.result:
Updated the result file after fixing bug#44331
mysql-test/suite/rpl/t/rpl_events.test:
Added test to verify if the definer is consistent between master and slave
when the event is created without the DEFINER clause set explicitly or the
DEFINER is set to CURRENT_USER
sql/events.cc:
The "create_query_string" function is added to create a new query string
for removing executable comments.
sql/sql_yacc.yy:
The remember_name token was added for recording the offset of EVENT_SYM.
Slave does not correctly handle "expected errors" leading to inconsistencies
between the mater and slave. Specifically, when a statement changes both
transactional and non-transactional tables, the transactional changes are
automatically rolled back on the master but the slave ignores the error and
does not roll them back thus leading to inconsistencies.
To fix the problem, we automatically roll back a statement that fails on
the slave but note that the transaction is not rolled back unless a "rollback"
command is in the relay log file.
mysql-test/extra/rpl_tests/rpl_mixing_engines.test:
Enabled item 13.e which was disabled because of the bug fixed by the
current and removed item 14 which was introduced by mistake.
binlog
Mixing transactional (T) and non-transactional (N) tables on behalf of a
transaction may lead to inconsistencies among masters and slaves in STATEMENT
mode. The problem stems from the fact that although modifications done to
non-transactional tables on behalf of a transaction become immediately visible
to other connections they do not immediately get to the binary log and therefore
consistency is broken. Although there may be issues in mixing T and M tables in
STATEMENT mode, there are safe combinations that clients find useful.
In this bug, we fix the following issue. Mixing N and T tables in multi-level
(e.g. a statement that fires a trigger) or multi-table table statements (e.g.
update t1, t2...) were not handled correctly. In such cases, it was not possible
to distinguish when a T table was updated if the sequence of changes was N and T.
In a nutshell, just the flag "modified_non_trans_table" was not enough to reflect
that both a N and T tables were changed. To circumvent this issue, we check if an
engine is registered in the handler's list and changed something which means that
a T table was modified.
Check WL 2687 for a full-fledged patch that will make the use of either the MIXED or
ROW modes completely safe.
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
Truncate statement is wrapped in BEGIN/COMMIT.
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
Truncate statement is wrapped in BEGIN/COMMIT.
In STATEMENT based replication, a statement that failed on the master but that
updated non-transactional tables is written to binary log with the error code
appended to it. On the slave, the statement is executed and the same error is
expected. However, when an "expected error" did not happen on the slave and was
either ignored or was related to a concurrency issue on the master, the slave
did not rollback the effects of the statement and as such inconsistencies might
happen.
To fix the problem, we automatically rollback a statement that should have
failed on a slave but succeded and whose expected failure is either ignored or
stems from a concurrency issue on the master.
If the log_bin_trust_function_creators option is not defined, creating a stored
function requires either one of the modifiers DETERMINISTIC, NO SQL, or READS
SQL DATA. Executing a stored function should also follows the same rules if in
STATEMENT mode. However, this was not happening and a wrong error was being
printed out: ER_BINLOG_ROW_RBR_TO_SBR.
The patch makes the creation and execution compatible and prints out the correct
error ER_BINLOG_UNSAFE_ROUTINE when a stored function without one of the modifiers
above is executed in STATEMENT mode.
to wrong result
When using MIXED mode and issuing 'CREATE TEMPORARY TABLE t_tmp',
the statement is logged if the current binlogging mode is
STATEMENT. This causes the slave to replay the instruction and
create the temporary table as well. If there is no switch to ROW
mode, and later on a 'DROP TEMPORARY TABLE t_tmp' is issued, then
this statement will also be logged and the slave will
remove/close the temporary table.
However, if there is a switch to ROW mode between the CREATE and
DROP TEMPORARY table, the DROP statement will not be logged,
leaving the slave with a dangling temporary table.
This patch addresses this, by always logging a DROP TEMPORARY
TABLE IF EXISTS when in mixed mode and a drop statement is issued
for temporary table(s).
mysql-test/suite/rpl/r/rpl_temp_table_mix_row.result:
Updated result file.
mysql-test/suite/rpl/t/rpl_temp_table_mix_row.test:
Added test case.
sql/sql_table.cc:
When dropping table(s) in mixed mode and current statement
logging is ROW, builds an extra DROP TEMPORARY TABLE IF
EXISTS for temporary tables that are being dropped. Later,
it logs the extra drop statement.
binlog
The fix for BUG 43929 introduced a regression issue. In a nutshell, when a
statement that changes a non-transactional table fails, it is written to the
binary log with the error code appended. Unfortunately, after BUG 43929, this
failure was flushing the transactional chace causing mismatch between execution
and logging histories. To fix this issue, we avoid flushing the transactional
cache when a commit or rollback is not issued.
The "get_master_version_and_clock(...)" function in sql/slave.cc ignores
error and passes directly when queries fail, or queries succeed
but the result retrieved is empty.
The "get_master_version_and_clock(...)" function should try to reconnect master
if queries fail because of transient network problems, and fail otherwise.
The I/O thread should print a warning if the some system variables do not
exist on master (very old master)
mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test:
Added test file for bug #45214
mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result:
Added test result for bug #45214
mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test:
Added test file for bug #45214
sql/slave.cc:
The 'is_network_error()' function is added for checking if the error is caused by network.
Added a new return value (2) to 'get_master_version_and_clock()' function result set
to indicate transient network errors when queries fail, and the caller should
try to reconnect in this case.
There is an inconsistency with DROP DATABASE|TABLE|EVENT IF EXISTS and
CREATE DATABASE|TABLE|EVENT IF NOT EXISTS. DROP IF EXISTS statements are
binlogged even if either the DB, TABLE or EVENT does not exist. In
contrast, Only the CREATE EVENT IF NOT EXISTS is binlogged when the EVENT
exists.
This patch fixes the following cases for all the replication formats:
CREATE DATABASE IF NOT EXISTS.
CREATE TABLE IF NOT EXISTS,
CREATE TABLE IF NOT EXISTS ... LIKE,
CREAET TABLE IF NOT EXISTS ... SELECT.
sql/sql_insert.cc:
Part of the code was moved from the create_table_from_items to select_create::prepare.
When replication is row based, CREATE TABLE IF NOT EXISTS.. SELECT is binlogged if the table exists.
timeout
In STMT and MIXED modes, a statement that changes both non-transactional and
transactional tables must be written to the binary log whenever there are
changes to non-transactional tables. This means that the statement gets into the
binary log even when the changes to the transactional tables fail. In particular
, in the presence of a failure such statement is annotated with the error number
and wrapped in a begin/rollback. On the slave, while applying the statement, it
is expected the same failure and the rollback prevents the transactional changes
to be persisted.
Unfortunately, statements that fail due to concurrency issues (e.g. deadlocks,
timeouts) are logged in the same way causing the slave to stop as the statements
are applied sequentially by the SQL Thread. To fix this bug, we automatically
ignore concurrency failures on the slave. Specifically, the following failures
are ignored: ER_LOCK_WAIT_TIMEOUT, ER_LOCK_DEADLOCK and ER_XA_RBDEADLOCK.
Large transactions and statements may corrupt the binary log if the size of the
cache, which is set by the max_binlog_cache_size, is not enough to store the
the changes.
In a nutshell, to fix the bug, we save the position of the next character in the
cache before starting processing a statement. If there is a problem, we simply
restore the position thus removing any effect of the statement from the cache.
Unfortunately, to avoid corrupting the binary log, we may end up loosing changes
on non-transactional tables if they do not fit in the cache. In such cases, we
store an Incident_log_event in order to stop the slave and alert users that some
changes were not logged.
Precisely, for every non-transactional changes that do not fit into the cache,
we do the following:
a) the statement is *not* logged
b) an incident event is logged after committing/rolling back the transaction,
if any. Note that if a failure happens before writing the incident event to
the binary log, the slave will not stop and the master will not have reported
any error.
c) its respective statement gives an error
For transactional changes that do not fit into the cache, we do the following:
a) the statement is *not* logged
b) its respective statement gives an error
To work properly, this patch requires two additional things. Firstly, callers to
MYSQL_BIN_LOG::write and THD::binlog_query must handle any error returned and
take the appropriate actions such as undoing the effects of a statement. We
already changed some calls in the sql_insert.cc, sql_update.cc and sql_insert.cc
modules but the remaining calls spread all over the code should be handled in
BUG#37148. Secondly, statements must be either classified as DDL or DML because
DDLs that do not get into the cache must generate an incident event since they
cannot be rolled back.
The server was not cleaning the last IO error and error number when
resetting slave.
This patch addresses this issue by backporting into 5.1 part of the
patch in BUG 34654. A fix for this issue had already been pushed into
6.0 as part of the aforementioned bug, however the patch also included
some refactoring. The fix for 5.1 does not take into account the
refactoring part.
mysql-test/extra/rpl_tests/rpl_reset_slave.test:
Backported the test case and improved with deploying include/start_slave.inc
in relevant spots.
sql/slave.cc:
Backported part of patch from 6.0 that includes cleaning
mi->clear_error() at:
1. beginning of handle_slave_io
2. on successful connection
Also, backported the assertion added in the original patch.
sql/sql_repl.cc:
Backported the call to mi->clear_error() on reset_slave().
Certain multi-updates gave different results on InnoDB from
to MyISAM, due to on-the-fly updates being used on the former and
the update order matters.
Fixed by turning off on-the-fly updates when update order
dependencies are present.
mysql-test/r/innodb_mysql.result:
Bug#43580: Test result.
mysql-test/suite/rpl/r/rpl_slave_skip.result:
Bug#43580: Changed test result. The InnoDB result is now what it would have been on MyISAM.
mysql-test/t/innodb_mysql.test:
Bug#43580: Test case.
sql/sql_base.cc:
Bug#43580: Added a word of caution about using tmp_set here.
sql/sql_update.cc:
Bug#43580: Fix.
Calls to TABLE::mark_columns_needed_for_update() are moved
from mysql_multi_update_prepare() and right before the decison
to do on-the-fly updates to the place where we do (or don't do)
on-the-fly updates.
In order to define the --slave-load-tmpdir, the init_relay_log_file()
was calling fn_format(MY_PACK_FILENAME) which internally was indirectly
calling strmov_overlapp() (through pack_dirname) and the following
warning message was being printed out while running in Valgrind:
"source and destination overlap in strcpy".
We fixed the issue by removing the flag MY_PACK_FILENAME as it was not
necessary. In a nutshell, with this flag the function fn_format() tried
to replace a directory by either "~", "." or "..". However, we wanted
exactly to remove such strings.
In this patch, we also refactored the functions init_relay_log_file()
and check_temp_dir(). The former was refactored to call the fn_format()
with the flag MY_SAFE_PATH along with the MY_RETURN_REAL_PATH, in order
to avoid issues with long directories and return an absolute path,
respectively. The flag MY_SAFE_UNPACK_FILENAME was removed too as it was
responsible for removing "~", "." or ".." only from the file parameter
and we wanted to remove such strings from the directory parameter in
the fn_format(). This result is stored in an rli variable, which is then
processed by the other function in order to verify if the directory exists
and if we are able to create files in it.
mysql-test/suite/rpl/t/rpl_slave_load_tmpdir_not_exist.test:
Changed the output to make it consistent among different runs.
mysys/mf_format.c:
Replaced a return for DBUG_RETURN.
Bug#319 if while a non-transactional slave is replicating a transaction possible problem
only testing related: addressing reviewers' comments.
mysql-test/suite/bugs/r/rpl_bug38205.result:
new results.
mysql-test/suite/bugs/t/rpl_bug38205.test:
changing output per reviewer's offering.
mysql-test/suite/rpl/r/rpl_start_stop_slave.result:
new results.
mysql-test/suite/rpl/t/rpl_start_stop_slave.test:
refining tests for Bug #38205, Bug#319 to start slave with the necessary synchronization;
changing output per reviewer's offering;
removing redundant wait for stop.
