When we write 'query=...' string to a frm file for views on a slave,
indentifiers are not properly quoted due to missing OPTION_QUOTE_SHOW_CREATE
flag in the thd->options.
Fix: properly set thd->options for the slave thread.
should be a separate module (i.e. a class) to make it easier to maintain the
code, e.g. by having checks within the rli checking sanity of data and making
member variables private. This will also ease implementation of multi-source
and, at least in my fantasies :), make it possible in some future to have
separate replication servers.
Transaction on the slave sql thread got blocked against a slave's mysqld local ta's
lock. Since the default, slave-transaction-retries=10, there was replaying of the
replicated ta. That failed because of a new started from 5.0.13 policy not to rollback
a timed-out transaction. Effectively the first round of a timed-out ta becomes committed
by the replaying's first "BEGIN".
It was decided to backport already existed method working in 5.1 implemented in
bug #16228 for handling symmetrical deadlock problem. That patch introduced end_trans
execution whenever a replicated ta deadlocks or timed-out.
Note, that this solution can be practically suboptimal - in the light of the changed behavior
due to timeout we still could replay only the last statement - only with a high rate of timeouting
replicated transactions.
Removing code to step the group log position and just stepping
the event log position. If the group log position were stepped
one time too many, it might be that the group starts at a position
that is not possible, e.g., at a Rows_log_event, or between an
Intvar_log_event and the following associated Query_log_event.
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.
BUG#20850: Assert during slave shutdown in many rpl_* tests.
This was caused by a race condition at the end of handle_slave_io
which under some circumstances allowed the cleanup to proceed before
the thread had completed.
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.
Added missing DBUG_xxx_RETURN statements
Fixed some usage of not initialized variables (as found by valgrind)
Ensure that we don't remove locked tables used as name locks from open table cache until unlock_table_names() are called.
This was fixed by having drop_locked_name() returning any table used as a name lock so that we can free it in unlock_table_names()
This will allow Tomas to continue with his work to use namelocks to syncronize things.
Note: valgrind still produces a lot of warnings about using not initialized code and shows memory loss errors when running the ndb tests
Transaction aborted on slave should be retries. The OPTION_BEGIN
bit was cleared prematurely. Removed dependence of code on value
of OPTION_BEGIN bit when executing retries.
