------------------------------------------------------------
revno: 2630.13.16
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: WL#4284
timestamp: Sat 2008-07-26 13:38:20 -0300
message:
WL#4284: Transactional DDL locking
SQL statements' effect on transactions.
Currently the MySQL server and its storage engines are not
capable of rolling back operations that define or modify data
structures (also known as DDL statements) or operations that
alter any of the system tables (the mysql database). Allowing
these group of statements to participate in transactions
is unfeasible at this time (since rollback has no effect
whatsoever on them) and goes against the design of our metadata
locking subsystem.
The solution is to issue implicit commits before and after
those statements execution. This effectively confines each of
those statements to its own special transaction and ensures
that metadata locks taken during this special transaction
are not leaked into posterior statements/transactions.
------------------------------------------------------------
revno: 2630.9.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 08:33:36 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
Changed close_cached_tables() not to flush all unused TABLE
instances when flushing individual table.
Renamed expel_table_from_cache() to tdc_remove_table() and
added enum parameter to be able more explicitly specify type
of removal, rewrote its code to be more efficient.
******
Backport of:
------------------------------------------------------------
revno: 2630.9.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 15:53:53 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After-review fixes in progress.
Minor changes in order to improve code readability
and simplify debugging.
------------------------------------------------------------
revno: 2630.8.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w4
timestamp: Thu 2008-06-05 10:48:36 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After-review fixes in progress.
Adjust some comments that were using old terminology
(name locks instead of exclusive metadata locks), brought
some of them up-to-date with current situation in code.
------------------------------------------------------------
revno: 2630.4.17
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-05-29 16:52:56 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
"The great correction of names".
Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of
these names in metadata locking subsystem consistent with
other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA
corresponds to request for a lock and MDL_LOCK to the lock
itself. Adjusted code in MDL subsystem and other places
using these classes accordingly.
Did similar thing for GLOBAL_MDL_LOCK_DATA class and also
changed name of its members to correspond to names of
MDL_LOCK_DATA members.
Finally got rid of usage of one letter variables in MDL
code since it makes code harder to search in (according
to reviewer).
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
------------------------------------------------------------
This is the first patch in series. It transforms the metadata
locking subsystem to use a dedicated module (mdl.h,cc). No
significant changes in the locking protocol.
The import passes the test suite with the exception of
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.
This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
WL#3726 "DDL locking for all metadata objects"
Fixed failing Windows builds by adding mdl.cc to the lists
of files needed to build server/libmysqld on Windows.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Fix for assert failures in kill.test which occured when one
tried to kill ALTER TABLE statement on merge table while it
was waiting in wait_while_table_is_used() for other connections
to close this table.
These assert failures stemmed from the fact that cleanup code
in this case assumed that temporary table representing new
version of table was open with adding to THD::temporary_tables
list while code which were opening this temporary table wasn't
always fulfilling this.
This patch changes code that opens new version of table to
always do this linking in. It also streamlines cleanup process
for cases when error occurs while we have new version of table
open.
******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Addition to the fix of assert failures in kill.test caused by
changes for this worklog.
Make sure we close the new table only once.
----------------------------------------------------------------------
ChangeSet@1.2571, 2008-04-08 12:30:06+02:00, vvaintroub@wva. +122 -0
Bug#32082 : definition of VOID in my_global.h conflicts with Windows
SDK headers
VOID macro is now removed. Its usage is replaced with void cast.
In some cases, where cast does not make much sense (pthread_*, printf,
hash_delete, my_seek), cast is ommited.
In RBR, All statements operating on temporary tables should not be binlogged.
Despite this fact, after executing 'TRUNCATE... ' on a temporary table,
the command is still logged, even if in row-based mode. Consequently, this raises
problems in the slave as the table may not exist, resulting in an
execution failure. Ultimately, this causes the slave to report
an error and abort.
After this patch, 'TRUNCATE ...' statement on a temporary table will not be
binlogged in RBR.
This is the non-ndb part of the patch.
The return value of mysql_bin_log.write was ignored by most callers,
which may lead to inconsistent on master and slave if the transaction
was committed while the binlog was not correctly written. If
my_error() is call in mysql_bin_log.write, this could also lead to
assertion issue if my_ok() or my_error() is called after.
This fixed the problem by let the caller to check and handle the
return value of mysql_bin_log.write. This patch only adresses the
simple cases.
DELETE IGNORE
The ER_CANT_UPDATE_USED_TABLE_IN_SF_OR_TRG error was set in the
diagnostics area when it happened, but the DELETE cleanup code
never checked for a non-fatal error condition, thus trying to
set diag.area to "ok". This triggered an assert checking that
the diag.area was empty.
The fix was to test if there existed a non-fatal error condition
(thd->is_error() before ok'ing the operation.
Non-transactional updates that take place inside a transaction present problems
for logging because they are visible to other clients before the transaction
is committed, and they are not rolled back even if the transaction is rolled
back. It is not always possible to log correctly in statement format when both
transactional and non-transactional tables are used in the same transaction.
In the current patch, we ensure that such scenario is completely safe under the
ROW and MIXED modes.
Implemented the server infrastructure for the fix:
1. Added a function LEX_STRING *thd_query_string(THD) to return
a LEX_STRING structure instead of char *.
This is the function that must be called in innodb instead of
thd_query()
2. Did some encapsulation in THD : aggregated thd_query and
thd_query_length into a LEX_STRING and made accessor and mutator
methods for easy code updating.
3. Updated the server code to use the new methods where applicable.
trigger, merge table
The problem with break statements is that they have very
local effects. Hence a break statement within the inner loop
of a nested-loops join caused execution to proceed to the
next table even though a serious error occurred. The problem
was fixed by breaking out the inner loop into its own
method. The change empowers all errors to terminate the
execution.
The errors that will now halt multi-DELETE execution
altogether are
- triggers returning errors
- handler errors
- server being killed
(temporary) TABLE, crash
Problem: if one has an open "HANDLER t1", further "TRUNCATE t1"
doesn't close the handler and leaves handler table hash in an
inconsistent state, that may lead to a server crash.
Fix: TRUNCATE should implicitly close all open handlers.
Doc. request: the fact should be described in the manual accordingly.
NOTE: This undoes changes by BUG#42829 in sql_class.cc:binlog_query().
I will revert the change in a post-push fix (the binlog filter should
be checked in sql_base.cc:decide_logging_format()).
General overview:
The logic for switching to row format when binlog_format=MIXED had
numerous flaws. The underlying problem was the lack of a consistent
architecture.
General purpose of this changeset:
This changeset introduces an architecture for switching to row format
when binlog_format=MIXED. It enforces the architecture where it has
to. It leaves some bugs to be fixed later. It adds extensive tests to
verify that unsafe statements work as expected and that appropriate
errors are produced by problems with the selection of binlog format.
It was not practical to split this into smaller pieces of work.
Problem 1:
To determine the logging mode, the code has to take several parameters
into account (namely: (1) the value of binlog_format; (2) the
capabilities of the engines; (3) the type of the current statement:
normal, unsafe, or row injection). These parameters may conflict in
several ways, namely:
- binlog_format=STATEMENT for a row injection
- binlog_format=STATEMENT for an unsafe statement
- binlog_format=STATEMENT for an engine only supporting row logging
- binlog_format=ROW for an engine only supporting statement logging
- statement is unsafe and engine does not support row logging
- row injection in a table that does not support statement logging
- statement modifies one table that does not support row logging and
one that does not support statement logging
Several of these conflicts were not detected, or were detected with
an inappropriate error message. The problem of BUG#39934 was that no
appropriate error message was written for the case when an engine
only supporting row logging executed a row injection with
binlog_format=ROW. However, all above cases must be handled.
Fix 1:
Introduce new error codes (sql/share/errmsg.txt). Ensure that all
conditions are detected and handled in decide_logging_format()
Problem 2:
The binlog format shall be determined once per statement, in
decide_logging_format(). It shall not be changed before or after that.
Before decide_logging_format() is called, all information necessary to
determine the logging format must be available. This principle ensures
that all unsafe statements are handled in a consistent way.
However, this principle is not followed:
thd->set_current_stmt_binlog_row_based_if_mixed() is called in several
places, including from code executing UPDATE..LIMIT,
INSERT..SELECT..LIMIT, DELETE..LIMIT, INSERT DELAYED, and
SET @@binlog_format. After Problem 1 was fixed, that caused
inconsistencies where these unsafe statements would not print the
appropriate warnings or errors for some of the conflicts.
Fix 2:
Remove calls to THD::set_current_stmt_binlog_row_based_if_mixed() from
code executed after decide_logging_format(). Compensate by calling the
set_current_stmt_unsafe() at parse time. This way, all unsafe statements
are detected by decide_logging_format().
Problem 3:
INSERT DELAYED is not unsafe: it is logged in statement format even if
binlog_format=MIXED, and no warning is printed even if
binlog_format=STATEMENT. This is BUG#45825.
Fix 3:
Made INSERT DELAYED set itself to unsafe at parse time. This allows
decide_logging_format() to detect that a warning should be printed or
the binlog_format changed.
Problem 4:
LIMIT clause were not marked as unsafe when executed inside stored
functions/triggers/views/prepared statements. This is
BUG#45785.
Fix 4:
Make statements containing the LIMIT clause marked as unsafe at
parse time, instead of at execution time. This allows propagating
unsafe-ness to the view.
without error
When using quick access methods for searching rows in UPDATE or
DELETE there was no check if a fatal error was not already sent
to the client while evaluating the quick condition.
As a result a false OK (following the error) was sent to the
client and the error was thus transformed into a warning.
Fixed by checking for errors sent to the client during
SQL_SELECT::check_quick() and treating them as real errors.
Fixed a wrong test case in group_min_max.test
Fixed a wrong return code in mysql_update() and mysql_delete()
The problem: described in the bug report.
The fix:
--increase buffers where it's necessary
(buffers which are used in stxnmov)
--decrease buffer lengths which are used
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.
with gcc 4.3.2
Compiling MySQL with gcc 4.3.2 and later produces a number of
warnings, many of which are new with the recent compiler
versions.
This bug will be resolved in more than one patch to limit the
size of changesets. This is the second patch, fixing more
of the warnings.
with gcc 4.3.2
Compiling MySQL with gcc 4.3.2 and later produces a number of
warnings, many of which are new with the recent compiler
versions.
This bug will be resolved in more than one patch to limit the
size of changesets. This is the second patch, fixing more
of the warnings.
Make the caller of Query_log_event, Execute_load_log_event
constructors and THD::binlog_query to provide the error code
instead of having the constructors to figure out the error code.
with seg fault
Multiple-table DELETE from a table joined to itself may cause
server crash. This was originally discovered with MEMORY engine,
but may affect other engines with different symptoms.
The problem was that the server violated SE API by performing
parallel table scan in one handler and removing records in
another (delete on the fly optimization).
on 5.0
The server crashes on an assert in net_end_statement indicating that the
Diagnostics area wasn't set properly during execution.
This happened on a multi table DELETE operation using the IGNORE keyword.
The keyword is suppose to allow for execution to continue on a best effort
despite some non-fatal errors. Instead execution stopped and no client
response was sent which would have led to a protocol error if it hadn't been
for the assert.
This patch corrects this issue by checking for the existence of an IGNORE
option before setting an error state during row-by-row delete iteration.
When the thread executing a DDL was killed after finished its
execution but before writing the binlog event, the error code in
the binlog event could be set wrongly to ER_SERVER_SHUTDOWN or
ER_QUERY_INTERRUPTED.
This patch fixed the problem by ignoring the kill status when
constructing the event for DDL statements.
This patch also included the following changes in order to
provide the test case.
1) modified mysqltest to support variable for connection command
2) modified mysql-test-run.pl, add new variable MYSQL_SLAVE to
run mysql client against the slave mysqld.
TRUNCATE TABLE fails to replicate when stmt-based binlogging is not supported.
There were two separate problems with the code, both of which are fixed with
this patch:
1. An error was printed by InnoDB for TRUNCATE TABLE in statement mode when
the in isolation levels READ COMMITTED and READ UNCOMMITTED since InnoDB
does permit statement-based replication for DML statements. However,
the TRUNCATE TABLE is not transactional, but is a DDL, and should therefore
be allowed to be replicated as a statement.
2. The statement was not logged in mixed mode because of the error above, but
the error was not reported to the client.
This patch fixes the problem by treating TRUNCATE TABLE a DDL, that is, it is
always logged as a statement and not reporting an error from InnoDB for TRUNCATE
TABLE.
When using CREATE TEMPORARY TABLE LIKE to create a temporary table,
or using TRUNCATE to delete all rows of a temporary table, they
did not set the tmp_table_used flag, and cause the omission of
"SET @@session.pseudo_thread_id" when dumping binlog with mysqlbinlog,
and cause error when replay the statements.
This patch fixed the problem by setting tmp_table_used in these two
cases. (Done by He Zhenxing 2009-01-12)
The special TRUNCATE TABLE (DDL) transaction wasn't being properly
rolled back if a error occurred during row by row deletion. The
error can be caused by a foreign key restriction imposed by InnoDB
SE and would cause the server to erroneously issue a implicit
commit.
The solution is to rollback the transaction if a truncation via row
by row deletion fails, otherwise commit. All effects of a TRUNCATE
ABLE operation are rolled back if a row by row deletion fails.
TRUNCATE TABLE for InnoDB tables returned a count showing an approximation
of the number of rows affected to gain efficiency.
Now the statement always returns 0 rows affected for clarity.
- In QUICK_INDEX_MERGE_SELECT::read_keys_and_merge: when we got table->sort from Unique,
tell init_read_record() not to use rr_from_cache() because a) rowids are already sorted
and b) it might be that the the data is used by filesort(), which will need record rowids
(which rr_from_cache() cannot provide).
- Fully de-initialize the table->sort read in QUICK_INDEX_MERGE_SELECT::get_next(). This fixes BUG#35477.
(bk trigger: file as fix for BUG#35478).
