This is a regression from the fix for bug no 38999. A storage engine capable
of reading only a subset of a table's columns updates corresponding bits in
the read buffer to signal that it has read NULL values for the corresponding
columns. It cannot, and should not, update any other bits. Bug no 38999
occurred because the implementation of UPDATE statements compare the NULL bits
using memcmp, inadvertently comparing bits that were never requested from the
storage engine. The regression was caused by the storage engine trying to
alleviate the situation by writing to all NULL bits, even those that it had no
knowledge of. This has devastating effects for the index merge algorithm,
which relies on all NULL bits, except those explicitly requested, being left
unchanged.
The fix reverts the fix for bug no 38999 in both InnoDB and InnoDB plugin and
changes the server's method of comparing records. For engines that always read
entire rows, we proceed as usual. For engines capable of reading only select
columns, the record buffers are now compared on a column by column basis. An
assertion was also added so that non comparable buffers are never read. Some
relevant copy-pasted code was also consolidated in a new function.
The subtime function wasn't able to produce correct int representation of
its result. For constant expressions the Item_datetime_cache is used to
speedup evaluation and Item_datetime_cache expects underlying item to return
correct int representation of DATETIME value. These two factors combined led
to a wrong query result.
Now the Item_func_add_time has function val_datetime which performs the
calculation and saves result into given MYSQL_TIME struct, it also sets
null_value to appropriate value. val_int and val_str member functions
convert the result obtained from val_datetime to int or string respectively
and returns it.
This change is to align the 5.5 performance_schema.THREADS
table definition with the 5.6 performance_schema.THREADS table,
to facilitate the 5.5 -> 5.6 migration later.
In the table performance_schema.THREADS:
- renamed ID to PROCESSLIST_ID, removed not null
- changed NAME from varchar(64) to varchar(128)
to match the columns definitions from 5.6
Adjusted the test cases accordingly.
Note: this fix is for 5.5 only, to null merge into 5.6
The fix is to:
- introduce ORACLE_WELCOME_COPYRIGHT_NOTICE define to have a single place
to specify copyright notice;
- replace custom copyright notices with ORACLE_WELCOME_COPYRIGHT_NOTICE
in programs.
Bug#54678: InnoDB, TRUNCATE, ALTER, I_S SELECT, crash or deadlock
- Incompatible change: truncate no longer resorts to a row by
row delete if the storage engine does not support the truncate
method. Consequently, the count of affected rows does not, in
any case, reflect the actual number of rows.
- Incompatible change: it is no longer possible to truncate a
table that participates as a parent in a foreign key constraint,
unless it is a self-referencing constraint (both parent and child
are in the same table). To work around this incompatible change
and still be able to truncate such tables, disable foreign checks
with SET foreign_key_checks=0 before truncate. Alternatively, if
foreign key checks are necessary, please use a DELETE statement
without a WHERE condition.
Problem description:
The problem was that for storage engines that do not support
truncate table via a external drop and recreate, such as InnoDB
which implements truncate via a internal drop and recreate, the
delete_all_rows method could be invoked with a shared metadata
lock, causing problems if the engine needed exclusive access
to some internal metadata. This problem originated with the
fact that there is no truncate specific handler method, which
ended up leading to a abuse of the delete_all_rows method that
is primarily used for delete operations without a condition.
Solution:
The solution is to introduce a truncate handler method that is
invoked when the engine does not support truncation via a table
drop and recreate. This method is invoked under a exclusive
metadata lock, so that there is only a single instance of the
table when the method is invoked.
Also, the method is not invoked and a error is thrown if
the table is a parent in a non-self-referencing foreign key
relationship. This was necessary to avoid inconsistency as
some integrity checks are bypassed. This is inline with the
fact that truncate is primarily a DDL operation that was
designed to quickly remove all data from a table.
A simple version of the patch : add WITH_PIC to debug compilation.
Engines that are not dependent on internal stuff (like THD structure)
will not be recompiled for embedded in debug mode.
Examples of such engines are : archive, federated, innodb. Engines
with dependencies on internals (myisam,heap,myisammrg) will still be
fully recompiled.
Problem: CASE didn't work with a mixture of different character
sets in THEN/ELSE in some cases.
This happened because after character set aggregation
newly created Item_func_conv_charset items corresponding
to THEN/ELSE arguments were not put back to args[] array.
Fix:
put all Item_func_conv_charset back to args[].
@ mysql-test/include/ctype_numconv.inc
@ mysql-test/r/ctype_ucs.result
Adding tests
@ sql/item_cmpfunc.cc
Put "agg" back to args[] after character set aggregation.
Suprisingly, a Slave_log_event would show up in the binary
log. This event is never used and should not appear in the
logs. As such, when the slave (or the mysqlbinlog tool) reads the
event, it will hit an invalid pointer (reference to the
descriptor event when deserializing the Slave_log_event was
purposodely set to NULL).
The presence of the Slave_log_event denotes a corrupted log, but
we cannot tell how the log got corrupted in the first
place. However, we can make the server cope with such events when
it reads them - in case of log corruption - and fail gracefully.
This patch makes the server/mysqlbinlog to report that it has
found an invalid log event when Slave_log_event is read.
thd->in_sub_stmt
In a precursor patch for Bug#52044
(revid:bzr/kostja@stripped), a
number of reorganizations of code was made. In addition some
assertions were added to ensure the correct transactional state.
The reorganization had a small glitch so statements that was
active in the query cache was not followed by a
statement commit/rollback (this code was removed). A section
in the trans_commit_stmt/trans_rollback_stmt code is to
clear the thd->transaction.stmt list of affected storage
engines. When a new statement is initiated, an assert
introduced by the 523044 patch checks if this list is cleared.
When the query cache is accessed, this list may be populated,
and since it's not committed it will not be cleared.
This fix adds explicit statement commit or rollback for
statements that is contained in the query cache.
for ALTER TABLE + MERGE tables
The patch for Bug#56292 changed how metadata locks are taken for MERGE
tables. After the patch, locking the MERGE table will also lock the
children tables with the same metadata lock type. This means that
LOCK TABLES on a MERGE table also will implicitly do LOCK TABLES on
the children tables.
A consequence of this change, is that it is possible to do LOCK TABLES
on a child table both explicitly and implicitly with the same statement
and that these two locks can be of different strength. For example,
LOCK TABLES child READ, merge WRITE.
In LOCK TABLES mode, we are not allowed to take new locks and each
statement must therefore try to find an existing TABLE instance with
a suitable lock. The code that searched for a suitable TABLE instance,
only considered table level locks. If a child table was locked twice,
it was therefore possible for this code to find a TABLE instance with
suitable table level locks but without suitable metadata lock.
This problem caused the assert in upgrade_shared_lock_to_exclusive()
to be triggered as it tried to upgrade a MDL_SHARED lock to
EXCLUSIVE. The problem was a regression caused by the patch for
Bug#56292.
This patch fixes the problem by partially reverting the changes
done by Bug#56292. Now, the children tables will only use the
same metadata lock as the MERGE table for MDL_SHARED_NO_WRITE
when not in locked tables mode. This means that LOCK TABLE
on a MERGE table will not implicitly lock the children tables.
This still fixes the original problem in Bug#56292 without
causing a regression.
Test case added to merge.test.
parameters don't match
Revert the changes of the default values of innodb_file_per_table
and innobase_file_format in 5.5, until WL#5135 is implemented.
error flushing io cache
The reason for the error was incorrect return code from
my_win_write() in case of error on 64 bit Windows.
Error should be indicated by return code
(size_t)-1 == 2^64 -1, but due to cast it was
(DWORD)-1 = 2^32 -1
The caller of this function would fail to recognize the error
and continue looping.
Fix is to return correct error code (size_t)-1 in case of error
as expected by caller.
Also minimal cleanup is done : my_win_write() now uses
the same parameter checks as related functions (0 and
overflow handling for count parameter).
- fix ~20 warnings about redefinition of HAVE_DLOPEN
This was caused by new ADD_DEFINITIONS(-DHAVE_DLOPEN) inside client library CMakeLists.txt
- fix dlerror() message which ("static build?" ) which is only confusing on Windows,
there is no "static build"
The error was introduced by typo in variable name (errormsg instead of correct
errmsg)
- Also, precache HAVE_PEERCRED to OFF in cmake\os\WindowsCache.cmake
(to avoid useless system check).
- Also, add missing check for errors from FormatMessage().
- Also, remove annoying CMake debug printout of MALLOC_LIB if this is not set.
connectors plugins
Implemented changes needed to keep the client plugin API compatible with
the existing plugins :
1. Provided an options() client plugin API to let the application pass
options to the plugin after loading it
2. Added "License" (const char *) to specify the client plugin's license
3. Added "mysql_api" as a placeholder that the client library can use
to pass function pointers to the plugin so that the plugin can call the
C lib back.
4. Updated the existing client plugins to comply with the API change.
5. Added more detailed error message generation for Windows.
Quoting from the bug report:
The pstack library has been included in MySQL since version
4.0.0. It's useless and should be removed.
Details: According to its own documentation, pstack only works
on Linux on x86 in 32 bit mode and requires LinuxThreads and a
statically linked binary. It doesn't really support any Linux
from 2003 or later and doesn't work on any other OS.