The slave was not able to find the correct row in the innodb
table, because the row fetched from the innodb table would not
match the before image. This happened because the (don't care)
bytes in the NULLed fields would change once the row was stored
in the storage engine (from zero to the default value). This
would make bulk memory comparison (using memcmp) to fail.
We fix this by taking a preventing measure and avoiding memcmp
for tables that contain nullable fields. Therefore, we protect
the slave search routine from engines that return arbitrary
values for don't care bytes (in the nulled fields). Instead, the
slave thread will only check null_bits and those fields that are
not set to NULL when comparing the before image against the
storage engine row.
In SBR, if a statement does not fail, it is always written to the binary
log, regardless if rows are changed or not. If there is a failure, a
statement is only written to the binary log if a non-transactional (.e.g.
MyIsam) engine is updated.
INSERT ON DUPLICATE KEY UPDATE and INSERT IGNORE were not following the
rule above and were not written to the binary log, if then engine was
Innodb.
Normally, auto_increment value is generated for the column by
inserting either NULL or 0 into it. NO_AUTO_VALUE_ON_ZERO
suppresses this behavior for 0 so that only NULL generates
the auto_increment value. This behavior is also followed by
a slave, specifically by the SQL Thread, when applying events
in the statement format from a master. However, when applying
events in the row format, the flag was ignored thus causing
an assertion failure:
"Assertion failed: next_insert_id == 0, file .\handler.cc"
In fact, we never need to generate a auto_increment value for
the column when applying events in row format on slave. So we
don't allow it to happen by using 'MODE_NO_AUTO_VALUE_ON_ZERO'.
Refactoring: Get rid of all the sql_mode checks to rows_log_event
when applying it for avoiding problems caused by the inconsistency
of the sql_mode on slave and master as the sql_mode is not set for
Rows_log_event.
Major replication test framework cleanup. This does the following:
- Ensure that all tests clean up the replication state when they
finish, by making check-testcase check the output of SHOW SLAVE STATUS.
This implies:
- Slave must not be running after test finished. This is good
because it removes the risk for sporadic errors in subsequent
tests when a test forgets to sync correctly.
- Slave SQL and IO errors must be cleared when test ends. This is
good because we will notice if a test gets an unexpected error in
the slave threads near the end.
- We no longer have to clean up before a test starts.
- Ensure that all tests that wait for an error in one of the slave
threads waits for a specific error. It is no longer possible to
source wait_for_slave_[sql|io]_to_stop.inc when there is an error
in one of the slave threads. This is good because:
- If a test expects an error but there is a bug that causes
another error to happen, or if it stops the slave thread without
an error, then we will notice.
- When developing tests, wait_for_*_to_[start|stop].inc will fail
immediately if there is an error in the relevant slave thread.
Before this patch, we had to wait for the timeout.
- Remove duplicated and repeated code for setting up unusual replication
topologies. Now, there is a single file that is capable of setting
up arbitrary topologies (include/rpl_init.inc, but
include/master-slave.inc is still available for the most common
topology). Tests can now end with include/rpl_end.inc, which will clean
up correctly no matter what topology is used. The topology can be
changed with include/rpl_change_topology.inc.
- Improved debug information when tests fail. This includes:
- debug info is printed on all servers configured by include/rpl_init.inc
- User can set $rpl_debug=1, which makes auxiliary replication files
print relevant debug info.
- Improved documentation for all auxiliary replication files. Now they
describe purpose, usage, parameters, and side effects.
- Many small code cleanups:
- Made have_innodb.inc output a sensible error message.
- Moved contents of rpl000017-slave.sh into rpl000017.test
- Added mysqltest variables that expose the current state of
disable_warnings/enable_warnings and friends.
- Too many to list here: see per-file comments for details.
win x86 debug_max
The windows MTR run exhibited a different test execution
ordering (due to the fact that in these platforms MTR is invoked
with --parallel > 1). This uncovered a bug in the aforementioned
test case, which is triggered by the following conditions:
1. server is not restarted between two different tests;
2. the test before binlog.binlog_row_failure_mixing_engines
issues flush logs;
3. binlog.binlog_row_failure_mixing_engines uses binlog
positions to limit the output of show_binlog_events;
4. binlog.binlog_row_failure_mixing_engines does not state which
binlog file to use, thence it uses a wrong binlog file with
the correct position.
There are two possible fixes: 1. make sure that the test start
from a clean slate - binlog wise; 2. in addition to the position,
also state the binary log file before sourcing
show_binlog_events.inc .
We go for fix#1, ie, deploy a RESET MASTER before the test is
actually started.
When using BINLOG statement to execute rows log events, session variables
foreign_key_checks and unique_checks are changed temporarily. As each rows
log event has their own special session environment and its own
foreign_key_checks and unique_checks can be different from current session
which executing the BINLOG statement. But these variables are not restored
correctly after BINLOG statement. This problem will cause that the following
statements fail or generate unexpected data.
In this patch, code is added to backup and restore these two variables.
So BINLOG statement will not affect current session's variables again.
replication aborts
When recieving a 'SLAVE STOP' command, slave SQL thread will roll back the
transaction and stop immidiately if there is only transactional table updated,
even through 'CREATE|DROP TEMPOARY TABLE' statement are in it. But These
statements can never be rolled back. Because the temporary tables to the user
session mapping remain until 'RESET SLAVE', Therefore it will abort SQL thread
with an error that the table already exists or doesn't exist, when it restarts
and executes the whole transaction again.
After this patch, SQL thread always waits till the transaction ends and then stops,
if 'CREATE|DROP TEMPOARY TABLE' statement are in it.
'CREATE TABLE IF NOT EXISTS ... SELECT' behaviour
BUG#55474, BUG#55499, BUG#55598, BUG#55616 and BUG#55777 are fixed
in this patch too.
This is the 5.1 part.
It implements:
- if the table exists, binlog two events: CREATE TABLE IF NOT EXISTS
and INSERT ... SELECT
- Insert nothing and binlog nothing on master if the existing object
is a view. It only generates a warning that table already exists.
With statement- or mixed-mode logging, "LOAD DATA INFILE" queries
are written to the binlog using special types of log events.
When mysqlbinlog reads such events, it re-creates the file in a
temporary directory with a generated filename and outputs a
"LOAD DATA INFILE" query where the filename is replaced by the
generated file. The temporary file is not deleted by mysqlbinlog
after termination.
To fix the problem, in mixed mode we go to row-based. In SBR, we
document it to remind user the tmpfile is left in a temporary
directory.
Add code to waiting for a set of errors.
Add code to waiting for an error instead of waiting for io thread to stop, as
after 'START SLAVE', the status of io thread is still not running.
But it doesn't mean slave io thread encounters an error.
Some of the test cases reference to binlog position and
these position numbers are written into result explicitly.
It is difficult to maintain if log event format changes.
There are a couple of cases explicit position number appears,
we handle them in different ways
A. 'CHANGE MASTER ...' with MASTER_LOG_POS or/and RELAY_LOG_POS options
Use --replace_result to mask them.
B. 'SHOW BINLOG EVENT ...'
Replaced by show_binlog_events.inc or wait_for_binlog_event.inc.
show_binlog_events.inc file's function is enhanced by given
$binlog_file and $binlog_limit.
C. 'SHOW SLAVE STATUS', 'show_slave_status.inc' and 'show_slave_status2.inc'
For the test cases just care a few items in the result of 'SHOW SLAVE STATUS',
only the items related to each test case are showed.
'show_slave_status.inc' is rebuild, only the given items in $status_items
will be showed.
'check_slave_is_running.inc' and 'check_slave_no_error.inc'
and 'check_slave_param.inc' are auxiliary files helping
to show running status and error information easily.
The test was used to fail because of
UPDATE t3,t4 SET t3.a=t4.a + bug27417(1);
did not prescribe the order of two row operations implied by the update.
Fixed with forcing the order with adding a where condition w/o
affecting the former bug fixes logics.
of sync
In RBR, sometimes the table->s->last_null_bit_pos can be zero. This
has impact at the slave when it compares records fetched from the
storage engine against records in the binary log event. If
last_null_bit_pos is zero the slave, while comparing in
log_event.cc:record_compare function, would set all bits in the last
null_byte to 1 (assumed all 8 were unused) . Thence it would loose the
ability to distinguish records that were similar in contents except
for the fact that some field was null in one record, but not in the
other. Ultimately this would cause wrong matches, and in the specific
case depicted in the bug report the same record would be updated
twice, resulting in a lost update.
Additionally, in the record_compare function the slave was setting the
X bit unconditionally. There are cases that the X bit does not exist
in the record header. This could also lead to wrong matches between
records.
We fix both by conditionally resetting the bits: (i) unused null_bits
are set if last_null_bit_pos > 0; (ii) X bit is set if
HA_OPTION_PACK_RECORD is in use.
DBUG_SYNC_POINT has at least one strong limitation that it's not defined
on all platforms. It has issues cooperating with @@debug.
All in all its functionality is superseded by DEBUG_SYNC facility and
there is no reason to maintain the old less flexible one.
Fixed with adding debug_sync_set_action() function as a facility to set up
a sync-action in the server sources code and re-writing existing simulations
(found 3) to use it.
Couple of tests have been reworked as well.
The patch offers a pattern for setting sync-points in replication threads
where the standard DEBUG_SYNC does not suffice to reach goals.
When using MyIsam tables and processing concurrent DML
statements, the server may be sending back an OK to the client
before actually finishing the transaction commit procedure. This
has been reported before in BUG@37521 and BUG@29334.
This particular test case gets affected, because it performs the
following sequence:
connect (conn2, ...)
connection conn2;
LOAD DATA CONCURRENT ...
disconnect (conn2, ...)
connection master;
sync_slave_with_master
diff_tables
At this point diff_tables may report difference in the table
content (the master seems to be missing the conn2 rows).
To workaround this MyISAM concurrent DML statements issue and
make this test case deterministic, we wait on conn2 until the
rows inserted show up in the table. After this the test case
proceeds as normally would before this patch.
Original revision:
------------------------------------------------------------
revision-id: li-bing.song@sun.com-20100130124925-o6sfex42b6noyc6x
parent: joro@sun.com-20100129145427-0n79l9hnk0q43ajk
committer: <Li-Bing.Song@sun.com>
branch nick: mysql-5.1-bugteam
timestamp: Sat 2010-01-30 20:49:25 +0800
message:
Bug #48321 CURRENT_USER() incorrectly replicated for DROP/RENAME USER;
REVOKE/GRANT; ALTER EVENT.
The following statements support the CURRENT_USER() where a user is needed.
DROP USER
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENT
but, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave
executes the log event, 'CURRENT_USER()' is expand to the user of slave
SQL thread, but SQL thread's user name always NULL. This breaks the replication.
After this patch, All above statements are rewritten when they are binlogged.
The CURRENT_USER() is expanded to the real user's name and host.
------------------------------------------------------------
REVOKE/GRANT; ALTER EVENT.
The following statements support the CURRENT_USER() where a user is needed.
DROP USER
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENT
but, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave
executes the log event, 'CURRENT_USER()' is expand to the user of slave
SQL thread, but SQL thread's user name always NULL. This breaks the replication.
After this patch, All above statements are rewritten when they are binlogged.
The CURRENT_USER() is expanded to the real user's name and host.
In RBR, DDL statement will change binlog format to non row-based
format before it is binlogged, but the binlog format was not be
restored, and then manipulating a temporary table can not reset binlog
format to row-based format rightly. So that the manipulated statement
is binlogged with statement-based format.
To fix the problem, restore the state of binlog format after the DDL
statement is binlogged.
cant find record
Some engines return data for the record. Despite the fact that
the null bit is set for some fields, their old value may still in
the row. This can happen when unpacking an AI from the binlog on
top of a previous record in which a field is set to NULL, which
previously contained a value. Ultimately, this may cause the
comparison of records to fail when the slave is doing an index or
range scan.
We fix this by deploying a call to reset() for each field that is
set to null while unpacking a row from the binary log.
Furthermore, we also add mixed mode test case to cover the
scenario where updating and setting a field to null through a
Query event and later searching it through a rows event will
succeed.
Finally, we also change the reset() method, from Field_bit class,
so that it takes into account bits stored among the null bits and
not only the ones stored in the record.
It is well-known that due to concurrency issues, a slave can become
inconsistent when a transaction contains updates to both transaction and
non-transactional tables in statement and mixed modes.
In a nutshell, the current code-base tries to preserve causality among the
statements by writing non-transactional statements to the txn-cache which
is flushed upon commit. However, modifications done to non-transactional
tables on behalf of a transaction become immediately visible to other
connections but may not immediately get into the binary log and therefore
consistency may be broken.
In general, it is impossible to automatically detect causality/dependency
among statements by just analyzing the statements sent to the server. This
happen because dependency may be hidden in the application code and it is
necessary to know a priori all the statements processed in the context of
a transaction such as in a procedure. Moreover, even for the few cases that
we could automatically address in the server, the computation effort
required could make the approach infeasible.
So, in this patch we introduce the option
- "--binlog-direct-non-transactional-updates" that can be used to bypass
the current behavior in order to write directly to binary log statements
that change non-transactional tables.
Problem: When RAND() is binlogged in statement mode, the seed is
binlogged too, so the replication slave generates the same
sequence of random numbers. This makes replication work in many
cases, but not in all cases: the order of rows is not guaranteed
for, e.g., UPDATE or INSERT...SELECT statements, so the row data
will be different if master and slave retrieve the rows in
different orders.
Fix: Mark RAND() as unsafe. It will generate a warning if
binlog_format=STATEMENT and switch to row-logging if
binlog_format=ROW.
'LOAD DATA CONCURRENT [LOCAL] INFILE ...' statment only is binlogged as
'LOAD DATA [LOCAL] INFILE ...' in SBR and MBR. As a result, if replication is on,
queries on slaves will be blocked by the replication SQL thread.
This patch write code to write 'CONCURRENT' into the log event if 'CONCURRENT' option
is in the original statement in SBR and MBR.
escaped field names
When in mixed or statement mode, the master logs LOAD DATA
queries by resorting to an Execute_load_query_log_event. This
event does not contain the original query, but a rewritten
version of it, which includes the table field names. However, the
rewrite does not escape the field names. If these names match a
reserved keyword, then the slave will stop with a syntax error
when executing the event.
We fix this by escaping the fields names as it happens already
for the table name.
Problem: Some system functions that could return different values on
master and slave were not marked unsafe. In particular:
GET_LOCK
IS_FREE_LOCK
IS_USED_LOCK
MASTER_POS_WAIT
RELEASE_LOCK
SLEEP
SYSDATE
VERSION
Fix: Mark these functions unsafe.
binlog, replication aborts
In SBR or MBR, the schema name is not being written to the binlog
when executing a LOAD DATA statement. This becomes a problem when
the current database (lets call it db1) is different from the
table's schema (lets call it db2). For instance, take the
following statements:
use db1;
load data local infile 'infile.txt' into table db2.t
Should this statement be logged without t's schema (db2), when
replaying it, one can get db1.t populated instead of db2.t (if
db1.t exists). On the other hand, if there is no db1.t at all,
replication will stop.
We fix this by always logging the table (in load file) with fully
qualified name when its schema is different from the current
database or when no default database was selected.
Backporting BUG#43789 to mysql-5.1-bugteam
The replication was generating corrupted data, warning messages on Valgrind
and aborting on debug mode while replicating a "null" to "not null" field.
Specifically the unpack_row routine, was considering the slave's table
definition and trying to retrieve a field value, where there was nothing to be
retrieved, ignoring the fact that the value was defined as "null" by the master.
To fix the problem, we proceed as follows:
1 - If it is not STRICT sql_mode, implicit default values are used, regardless
if it is multi-row or single-row statement.
2 - However, if it is STRICT mode, then a we do what follows:
2.1 If it is a transactional engine, we do a rollback on the first NULL that is
to be set into a NOT NULL column and return an error.
2.2 If it is a non-transactional engine and it is the first row to be inserted
with multi-row, we also return the error. Otherwise, we proceed with the
execution, use implicit default values and print out warning messages.
Unfortunately, the current patch cannot mimic the behavior showed by the master
for updates on multi-tables and multi-row inserts. This happens because such
statements are unfolded in different row events. For instance, considering the
following updates and strict mode:
(master)
create table t1 (a int);
create table t2 (a int not null);
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
t1 would have (10) and t2 would have (0) as this would be handled as a
multi-row update. On the other hand, if we had the following updates:
(master)
create table t1 (a int);
create table t2 (a int);
(slave)
create table t1 (a int);
create table t2 (a int not null);
(master)
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
On the master t1 would have (10) and t2 would have (NULL). On
the slave, t1 would have (10) but the update on t1 would fail.
Backporting BUG#38173 to mysql-5.1-bugteam
The reason of the bug was incompatibile with the master side behaviour.
INSERT query on the master is allowed to insert into a table without specifying
values of DEFAULT-less fields if sql_mode is not strict.
Fixed with checking sql_mode by the sql thread to decide how to react.
Non-strict sql_mode should allow Write_rows event to complete.
todo: warnings can be shown via show slave status, still this is a
separate rather general issue how to show warnings for the slave threads.
The BINLOG statement was sharing too much code with the slave SQL thread, introduced with
the patch for Bug#32407. This caused statements to be logged with the wrong server_id, the
id stored inside the events of the BINLOG statement rather than the id of the running
server.
Fix by rearranging code a bit so that only relevant parts of the code are executed by
the BINLOG statement, and the server_id of the server executing the statements will
not be overrided by the server_id stored in the 'format description BINLOG statement'.
