A communication packet can also be a binlog event sent from the master to the slave.
To be sent by master dump and accepted by slave io thread both have to have
the value of max_allowed_packet bigger than one that client connection had.
In the patch there is the MAX possible replicatio header size estimation for events
in binlog that embedded user query. Only these events of query_log_event type, i.e
just plain queries, require attention.
Fix when __attribute__() is stubbed out, add ATTRIBUTE_FORMAT() for specifying
__attribute__((format(...))) safely, make more use of the format attribute,
and fix some of the warnings that this turns up (plus a bonus unrelated one).
when calling a SP from C API"
The bug was caused by lack of checks for misuse in mysql_real_query.
A stored procedure always returns at least one result, which is the
status of execution of the procedure itself.
This result, or so-called OK packet, is similar to a result
returned by INSERT/UPDATE/CREATE operations: it contains the overall
status of execution, the number of affected rows and the number of
warnings. The client test program attached to the bug did not read this
result and ivnoked the next query. In turn, libmysql had no check for
such scenario and mysql_real_query was simply trying to send that query
without reading the pending response, thus messing up the communication
protocol.
The fix is to return an error from mysql_real_query when it's called
prior to retrieval of all pending results.
No test case as the bug is in an existing test case (rpl_trigger.test
when it is run under valgrind).
The warning was caused by memory corruption in replication slave: thd->db
was pointing at a stack address that was previously used by
sp_head::execute()::old_db. This happened because mysql_change_db
behaved differently in replication slave and did not make a copy of the
argument to assign to thd->db.
The solution is to always free the old value of thd->db and allocate a new
copy, regardless whether we're running in a replication slave or not.
Bug#19022 "Memory bug when switching db during trigger execution"
Bug#17199 "Problem when view calls function from another database."
Bug#18444 "Fully qualified stored function names don't work correctly in
SELECT statements"
Documentation note: this patch introduces a change in behaviour of prepared
statements.
This patch adds a few new invariants with regard to how THD::db should
be used. These invariants should be preserved in future:
- one should never refer to THD::db by pointer and always make a deep copy
(strmake, strdup)
- one should never compare two databases by pointer, but use strncmp or
my_strncasecmp
- TABLE_LIST object table->db should be always initialized in the parser or
by creator of the object.
For prepared statements it means that if the current database is changed
after a statement is prepared, the database that was current at prepare
remains active. This also means that you can not prepare a statement that
implicitly refers to the current database if the latter is not set.
This is not documented, and therefore needs documentation. This is NOT a
change in behavior for almost all SQL statements except:
- ALTER TABLE t1 RENAME t2
- OPTIMIZE TABLE t1
- ANALYZE TABLE t1
- TRUNCATE TABLE t1 --
until this patch t1 or t2 could be evaluated at the first execution of
prepared statement.
CURRENT_DATABASE() still works OK and is evaluated at every execution
of prepared statement.
Note, that in stored routines this is not an issue as the default
database is the database of the stored procedure and "use" statement
is prohibited in stored routines.
This patch makes obsolete the use of check_db_used (it was never used in the
old code too) and all other places that check for table->db and assign it
from THD::db if it's NULL, except the parser.
How this patch was created: THD::{db,db_length} were replaced with a
LEX_STRING, THD::db. All the places that refer to THD::{db,db_length} were
manually checked and:
- if the place uses thd->db by pointer, it was fixed to make a deep copy
- if a place compared two db pointers, it was fixed to compare them by value
(via strcmp/my_strcasecmp, whatever was approproate)
Then this intermediate patch was used to write a smaller patch that does the
same thing but without a rename.
TODO in 5.1:
- remove check_db_used
- deploy THD::set_db in mysql_change_db
See also comments to individual files.
Bad examples of usage of a string with its length fixed.
The incorrect length in the trigger file configuration descriptor
fixed (BUG#14090).
A hook for unknown keys added to the parser to support old .TRG files.
in short we now record whenever the slave I/O thread ignores a master's event because of its server id,
and use this info in the slave SQL thread to advance Exec_master_log_pos. Because if we
do not, this variable stays at the position of the last executed event, i.e. the last *non-ignored*
executed one, which may not be the last of the master's binlog (and so the slave *looks* behind
the master though it's data-wise it's not).
- CHAR() now returns binary string as default
- CHAR(X*65536+Y*256+Z) is now equal to CHAR(X,Y,Z) independent of the character set for CHAR()
- Test for both ETIMEDOUT and ETIME from pthread_cond_timedwait()
(Some old systems returns ETIME and it's safer to test for both values
than to try to write a wrapper for each old system)
- Fixed new introduced bug in NOT BETWEEN X and X
- Ensure we call commit_by_xid or rollback_by_xid for all engines, even if one engine has failed
- Use octet2hex() for all conversion of string to hex
- Simplify and optimize code
we now issue a warning (at slave's server startup only) when a relay log is named
using the implicit hostname-relay-bin naming. Like we already do for binlogs.
Some options were declared as 'bool', but since those are being
handled in my_getopt.c, bool can be machine dependent. To make
sure it works in all circumstances, the type should be my_bool
for C (not C++) programs.
present): the problem originally was that the tables in auxilliary_tables did not have
the correct real_name, which caused problems in the second call to tables_ok().
The fix corrects the real_name problem, and also sets the updating flag properly,
which makes the second call to tables_ok() unnecessary.
- Fixed some error condtion when handling dates with 'T'
- Added extra test for bug #11867 (Wrong result with "... WHERE ROW( a, b ) IN ( SELECT DISTINCT a, b WHERE ...)" to show it's not yet fixed
- Safety fixes and cleanups
Fixed portability problem with bool in C programs
Moved close_thread_tables out from LOCK_thread_count mutex (safety fix)
my_sleep() -> pthread_cond_timedwait()
ETIME was returned by cond_timedwait (sic, the pre-POSIX1001b function) on
Solaris 2.6 and 2.7. pthread_cond_timedwait on Solaris returns ETIMEDOUT.
The standard requirement is that the only additional return value
of pthred_cond_timedwait compared to pthread_cond_wait is ETIMEDOUT.
Let us not bloat the application code with redundant checks,
and if we're ever to work on a platform that returns a non-standard
value, we should write a wrapper for that platform (like we do, e.g., for
Windows).
Fix for yaSSL link failures with Forte Developer 7, MIPSpro Compilers, Compaq C++.
These compilers have problem with implicit template instantiation in archives
(libyassl.a, libtaocrypt.a). Instantiate templates explicitly.
Fix for yaSSL link failure on powermacg5 (gcc 3.3). When -O3 is specified gcc inlines
__cxa_pure_virtual. This is wrong behavior, __cxa_pure_virtual must never be inlined.
Approximative, because it's using our binlogging way (what we call "query"-level) and this is not as good as record-level binlog (5.1) would be. It imposes several
limitations to routines, and has caveats (which I'll document, and for which the server will try to issue errors but that is not always possible).
Reason I don't propagate caller info to the binlog as planned is that on master and slave
users may be different; even with that some caveats would remain.
s/sleep/safe_sleep (thread safe); sleep 0/1/2/3/4/5/5/5 (get slave less late);
no message on error log (deadlock is too common sometimes), a global counter
instead (SHOW STATUS LIKE 'slave_retried_transactions').
Plus a fix for libmysql/Makefile.shared
in slave SQL thread: if a transaction fails because of InnoDB deadlock or innodb_lock_wait_timeout exceeded,
optionally retry the transaction a certain number of times (new variable --slave_transaction_retries).
we store 7 bytes (1 + 2*3) in every Query_log_event.
In the future if users want binlog optimized for small size and less safe,
we could add --binlog-no-charset (and binlog-no-sql-mode etc): charset info
is something by design optional (even if for now we don't offer possibility to disable it):
it's not a binlog format change.
We try to reduce the number of get_charset() calls in the slave SQL thread to a minimum
by caching the charset read from the previous event (which will often be equal to the one of the current event).
We don't use SET ONE_SHOT for charset-aware repl (we still do for timezones, will be fixed later).
No more errors if one changes the global value of charset vars on master or slave
(as we log charset info in all Query_log_event).
Not fixing Load_log_event as it will be rewritten soon by Dmitri.
Testing how mysqlbinlog behaves in rpl_charset.test.
mysqlbinlog needs to know where charset file is (to be able to convert a charset number found
in binlog (e.g. in User_var_log_event) to a charset name); mysql-test-run needs to pass
the correct value for this option to mysqlbinlog.
Many result udpates (adding charset info into every event shifts log_pos in SHOW BINLOG EVENTS).
Roughly the same job is to be done for timezones :)
Split TABLE to TABLE and TABLE_SHARE (TABLE_SHARE is still allocated as part of table, will be fixed soon)
Created Field::make_field() and made Field_num::make_field() to call this
Added 'TABLE_SHARE->db' that points to database name; Changed all usage of table_cache_key as database name to use this instead
Changed field->table_name to point to pointer to alias. This allows us to change alias for a table by just updating one pointer.
Renamed TABLE_SHARE->real_name to table_name
Renamed TABLE->table_name to alias
Renamed TABLE_LIST->real_name to table_name
because old behaviour was somewhat nonsensical (kind of bug). Changes are that if repl threads are
down or disconnected the column will be NULL, and if master is idle the column will not grow indefinitely anymore.
All our programs which use mysql_real_connect() and mysql_connect() are updated accordingly, though I have deliberately
made mysqlimport not reconnect anymore (already true for mysqldump >= 4.1.8).
All Connector devs have been warned about the change I'm doing here - which was agreed with Monty,
and fixes BUG#2555.
1 if the return type is int or int_fast8_t. The test case that showed
this problem is rpl000001 and the tested version was MySQL 5.0.2. The
compiler with the problem is GCC 3.0.4 runing on "Linux bitch 2.4.18
#2 Thu Apr 11 14:37:17 EDT 2002 sparc64 unknown".
By changing the return type to bool the problem disappear. (Another
way to make the problem disappear is to simply print the returned
value with printf("%d",?). The printed returned value is always 0 in
the test cases I have run.) This is only a partial solution to the
problem, since someone could later change the return type of the
function back to int or some other type that does not work.
