Functionality Added or Changed
libedit library was upgraded to version
Using an XPath expression employing a scalar expression as a
UpdateXML() caused the server to
crash. Such expressions now cause an error instead.
The fix for Bug #33699 introduced a change to the
UPDATE statement such that
NULL to a
NULL column caused an error even when strict SQL mode
was not enabled. The original behavior before was that such
assignments caused an error only in strict SQL mode, and
otherwise set the column to the implicit default value for the
column data type and generated a warning. (For information about
implicit default values, see
Data Type Default Values.)
The change caused compatibility problems for applications that
relied on the original behavior. It also caused replication
problems between servers that had the original behavior and
those that did not, for applications that assigned
NOT NULL columns
UPDATE statements without
strict SQL mode enabled. This change has been reverted so that
UPDATE again had the original
behavior. Problems can still occur if you replicate between
servers that have the modified
UPDATE behavior and those that do
When using the MySQL Instance Configuration Wizard with a
configuration where you already have an existing installation
with a custom
datadir, the wizard could reset
the data to the default data directory. When performing an
upgrade installation in this situation, you must re-specify your
custom settings, including the
ensure that your configuration file is not reset to the default
Uninstalling MySQL using the MySQL installer on Windows would
my.ini file. The file is no longer
deleted. In addition, when a new installation is conducted, any
existing configuration file will be renamed to
myDATETIME.ini.bak during configuration.
Important Change: When installing MySQL on Windows, it was possible to install multiple editions (Complete, and Essential, for example) of the same version of MySQL, leading to two separate entries in the installed packages which were impossible to isolate. This could lead to problems with installation and uninstallation. The MySQL installer on Windows no longers permits multiple installations of the same version of MySQL on a single machine. (Bug #4217)
TRUNCATE TABLE statements failed
to replicate when statement-based binary logging mode was not
available. The issue was observed when using
InnoDB with the transaction
isolation level set to
READ UNCOMMITTED (thus
InnoDB not to permit
statement-based logging). However, the same behavior could be
reproduced using any transactional storage engine supporting
only row-based logging, regardless of the isolation level. This
was due to two separate problems:
An error was printed by
TRUNCATE TABLE when using
statement-based logging mode where the transaction isolation
level was set to
READ COMMITTED or
READ UNCOMMITTED, because
InnoDB permits statement-based
replication for DML statements. However,
TRUNCATE TABLE is not
transactional; since it is the equivalent of
DROP TABLE followed by
CREATE TABLE, it is actually
DDL, and should therefore be permitted to be replicated as a
TRUNCATE TABLE was not logged
in mixed mode because of the error just described; however,
this error was not reported to the client.
As a result of this fix,
TABLE is now treated as DDL for purposes of binary
logging and replication; that is, it is always logged as a
statement and so no longer causes an error when replicated using
a transactional storage engine such as
References: See also Bug #42643.
UNTIL did not work correctly with
enabled; when started with this option, the slave did not
perform events recorded in the relay log and that originated
from a different master.
Log rotation events are automatically generated and written when
rotating the binary log or relay log. Such events for relay logs
are usually ignored by the slave SQL thread because they have
the same server ID as that of the slave. However, when
enabled, the rotation event for the relay log was treated as if
it originated on the master, because the log's name and
position were incorrectly updated. This caused the
MASTER_POS_WAIT() function always
NULL and thus to fail.
(Bug #38734, Bug #38934)
In statement mode, mysqlbinlog failed to
SET @@autommit statement when the
autocommit mode was changed.
INFILE statements did not replicate correctly from a
master running MySQL 4.1 to a slave running MySQL 5.1 or later.
When using the MySQL MSI Installer on Windows and selecting Back after a choosing Repair, you would be returned to the Fresh Install section of the installer. You are now correctly returned to the Install, Repair, Modify screen. (Bug #37294)
MEMORY table became full,
the error generated was returned to the client but was not
written to the error log.
libmysqld was not built with all character
NULL testing in the
The query cache stored packets containing the server status of the time when the cached statement was run. This might lead to an incorrect transaction status on the client side if a statement was cached during a transaction and later served outside a transaction context (or vice versa). (Bug #36326)
The SSL certificates included with MySQL distributions were regenerated because the previous ones had expired. (Bug #42366)
The Windows installer displayed incorrect product names in some images. (Bug #40845)
ROW(...) IN (SELECT ... FROM
DUAL) always returned
User variables within triggers could cause a crash if the
mysql_change_user() C API
function was invoked.
NULL DEFAULT ... column, storing
NULL as the return value from some functions
caused a “cannot be NULL” error.
NULL returns now correctly cause the column
default value to be stored.
variable had no effect on the handling of
.frm files for views.
The query cache stored only partial query results if a statement failed while the results were being sent to the client. This could cause other clients to hang when trying to read the cached result. Now if a statement fails, the result is not cached. (Bug #40264)
The mysql client sometimes improperly interpreted string escape sequences in nonstring contexts. (Bug #36391)
If the system time was adjusted backward during query execution, the apparent execution time could be negative. But in some cases these queries would be written to the slow query log, with the negative execution time written as a large unsigned number. Now statements with apparent negative execution time are not written to the slow query log. (Bug #35396)
The greedy optimizer could cause a server crash due to improper handling of nested outer joins. (Bug #38795)
Dependent subqueries such as the following caused a memory leak proportional to the number of outer rows:
SELECT COUNT(*) FROM t1, t2 WHERE t2.b IN (SELECT DISTINCT t2.b FROM t2 WHERE t2.b = t1.a);
Some queries using
...) led to a server crash due to a failed type cast.
On the IBM i5 platform, the MySQL configuration process caused
the system version of
to be used. This function returns
i5 because it is not supported, causing the server to crash. Now
my_pthread_setprio() function in the
mysys library is used instead.
'%' character in SQL statements could cause
the server to crash.
The server cannot execute
statements when statement-based binary logging is enabled, but
the error message displayed only the table name, not the entire
FULLTEXT indexes did not work for Unicode
columns that used a custom UCA collation.
On Mac OS X, some of the universal client libraries were not actually universal and were missing code for one or more architectures. (Bug #41940)
An optimization introduced for Bug #37553 required an explicit
cast to be added for some uses of
TIMEDIFF() because automatic
casting could produce incorrect results. (It was necessary to
should be equivalent to setting the transaction isolation level
READ COMMITTED. However,
if both of those things were done, nonmatching semi-consistently
read rows were not unlocked when they should have been.
String reallocation could cause memory overruns. (Bug #41868)
For comparison of
NULL to a subquery result
IS NULL, the comparison could evaluate
NULL rather than to
occurred for expressions such as:
SELECT ... WHERE NULL IN (SELECT ...) IS NULL
runtime could cause errors.
InnoDB tables that used
ROW_FORMAT=REDUNDANT, storage size of
NULL columns could be determined incorrectly.
With row-based binary logging, replication of
InnoDB tables containing
BIT columns could fail.
The use by
libedit of the
__weak_reference() macro caused compilation
failure on FreeBSD.
mysql_install_db did not pass some relevant options to mysqld. (Bug #41828)
The embedded server truncated some error messages. (Bug #37995)
Attempts to open a valid
table sometimes resulted in a
ER_WRONG_MRG_TABLE error. This
happened after failure to open an invalid
MERGE table had also generated an
References: See also Bug #63524.
For Solaris package installation using
pkgadd, the postinstall script failed,
causing the system tables in the
database not to be created.