MySQL 5.6 Release Notes
Previously, enabling the
mysql_firewall_trace
system
variable caused MySQL Enterprise Firewall to write a file named
firewall_trace.txt
in the data directory.
That is no longer done. Now with
mysql_firewall_trace
enabled,
for PROTECTING
mode, the firewall writes
rejected statements to the error log.
my_print_defaults now masks passwords. To
display passwords in cleartext, use the new
--show
option.
(Bug #19953365, Bug #20903330)
MySQL Enterprise Firewall operates on parser states and does not work well together with the query cache, which circumvents the parser. MySQL Enterprise Firewall now checks whether the query cache is enabled. If so, it displays a message that the query cache must be disabled and does not load. (Bug #20913616)
MySQL distributions now include an
innodb_stress
suite of test cases. Thanks to
Mark Callaghan for the contribution.
(Bug #76347, Bug #20717127)
InnoDB; Partitioning:
The CREATE_TIME
column of the
INFORMATION_SCHEMA.TABLES
table now
shows the correct table creation time for partitioned
InnoDB
tables. The
CREATE_TIME
column of the
INFORMATION_SCHEMA.PARTITIONS
table
now shows the correct partition creation time for a partition of
partitioned InnoDB
tables.
The UPDATE_TIME
column of the
INFORMATION_SCHEMA.TABLES
table now shows
when a partitioned InnoDB
table was last
updated by an INSERT
,
DELETE
, or
UPDATE
. The
UPDATE_TIME
column of the
INFORMATION_SCHEMA.PARTITIONS
table now shows
when a partition of a partitioned InnoDB
table was last updated.
(Bug #69990, Bug #17299181)
InnoDB: An assertion was raised on shutdown due to XA PREPARE transactions holding explicit locks. (Bug #20816223, Bug #76567)
InnoDB:
The innodb_checksum_algorithm
strict_*
settings
(strict_none
,
strict_innodb
, and
strict_crc32
) caused the server to halt when
InnoDB
encountered a valid but non-matching
checksum. For example, with
innodb_checksum_algorithm=strict_crc32
, a
valid innodb
checksum would cause the server
to halt. Now, instead of halting the server,
InnoDB
only prints an error message.
(Bug #20568464)
InnoDB:
The memcached
set
command
permitted a negative expire time value. Expire time is stored
internally as an unsigned integer. A negative value would be
converted to a large number and accepted. The maximum expire
time value is now restricted to INT_MAX32
to
prevent negative expire time values.
(Bug #20478242, Bug #75790)
InnoDB: Removal of a foreign key object from the data dictionary cache during error handling caused the server to exit. (Bug #20442523)
InnoDB:
SHOW ENGINE INNODB STATUS
output showed
negative reservation and signal count values due to a counter
overflow error.
(Bug #20417397)
InnoDB: Failure to check the status of a cursor transaction read-only option before reusing the cursor transaction for a write operation resulted in a server exit during a memcached workload. (Bug #20391552)
InnoDB:
MDL locks taken by memcached clients caused a
MySQL Enterprise Backup FLUSH TABLES WITH READ
LOCK
operation to hang.
(Bug #20275612)
InnoDB: Estimates that were too low for the size of merge chunks in the result sorting algorithm caused a server exit. (Bug #20049521)
InnoDB: For full-text searches, the optimizer could choose an index that does not produce correct relevancy rankings. (Bug #74686, Bug #19950568)
Partitioning:
When creating a partitioned table, partition-level DATA
DIRECTORY
or INDEX DIRECTORY
option
values that contained an excessive number of characters were
handled incorrectly.
(Bug #20809045)
Partitioning:
Executing an ALTER TABLE
on a
partitioned table on which a write lock was in effect could
cause subsequent SQL statements on this table to fail.
(Bug #74288, Bug #74634, Bug #19784790, Bug #19918805)
References: See also: Bug #19856162, Bug #74451.
Replication:
Row unpacking did not function correctly in some cases when
running the server with
binlog_row_image
set to
minimal
.
(Bug #20468712)
Replication: When binary logging was enabled, using stored functions and triggers resulting in a long running procedure that inserted many records caused the memory use to increase rapidly. This was due to memory being allocated per variable. The fix ensures that in such a situation, memory is allocated once and the same memory is reused. (Bug #75879, Bug #20531812)
Replication: If an error was encountered while adding a GTID to the received GTID set, the log lock was not being correctly released. This could cause a deadlock. (Bug #75781, Bug #20492319)
Replication:
A slave running MySQL 5.6.24 or earlier could not connect to a
master running MySQL 5.7.6 and later that had
gtid_mode=OFF_PERMISSIVE
or
gtid_mode=ON_PERMISSIVE
. The
fix ensures that a slave running MySQL 5.6.25 and later can
connect to such a master as long as the slave's
gtid_mode
is compatible. In
other words, a slave running MySQL 5.6.25 and later which has
gtid_mode=OFF
can connect to a
master running MySQL 5.7.6 and later which has
gtid_mode=OFF_PERMISSIVE
, and a
slave running MySQL 5.6.25 and later which has
gtid_mode=ON
can connect to a
master running MySQL 5.7.6 and later which has
gtid_mode=ON_PERMISSIVE
. Other
combinations are incompatible.
(Bug #75769, Bug #20471216)
Replication:
If an error occurred when using a multithreaded slave, issuing a
CHANGE MASTER TO
statement which
resulted in an
ER_MTS_CHANGE_MASTER_CANT_RUN_WITH_GAPS
error, and then issuing RESET
SLAVE
, made it impossible to change master due to
repeated
ER_MTS_CHANGE_MASTER_CANT_RUN_WITH_GAPS
errors. Running the debug version of mysqld
caused an unexpected exit in this case. The fix ensures that the
recovery process for multithreaded slaves avoids this.
(Bug #75574, Bug #20411374)
Replication: When using semisynchronous replication performance was degrading when the number of threads increased beyond a certain threshold. To improve performance, now only the thread which is committing is responsible for deleting the active transaction node. All other operations do not touch this active transaction list. (Bug #75570, Bug #20574628)
Replication: Using mysqlbinlog to process log events greater than 1.6GB failed with an out of memory error. This was caused by an internal error converting the length variable. The fix upgrades the length variable to avoid overflow in both encoding and decoding functions. (Bug #74734, Bug #20350989)
Replication:
When
master_info_repository=TABLE
the receiver thread stores received event information in a
table. The memory used in the process of updating the table was
not being freed correctly and this could lead to an out of
memory error. The fix ensures that after an event is flushed to
the relay log file by a receiver thread, the memory used is
freed.
(Bug #72885, Bug #19390463, Bug #69848, Bug #20124342)
Replication:
Using mysqlbinlog to replay a relay log which
ended with GTID_LOG_EVENT
could cause the
following error:
ERROR 1790 (HY000) @@SESSION.GTID_NEXT cannot be
changed by a client that owns a GTID. The client owns
UUID:GTID
. Ownership is released on
COMMIT or ROLLBACK.
If a relay log rotate happens (either through a receiver thread
restart or after issuing the ROTATE
command)
exactly after writing a GTID_LOG_EVENT
, when
replaying such a relay log's end
ROTATE_EVENT
, it was mistakenly identified as
being inside a transaction, whereas the transaction was actually
started after GTID_LOG_EVENT
. This caused
mysqlbinlog to append SET
@@SESSION.GTID_NEXT='AUTOMATIC'
, resulting in two
GTID_NEXT
statements one after
the other. The fix ensures that mysqlbinlog
generates SET @@SESSION.GTID_NEXT='AUTOMATIC'
only outside of a transaction and when there has not been a
previous GTID_LOG_EVENT
.
Similarly, using mysqlbinlog to concatenate
and replay a relay log which contained a partial GTID
transaction caused the above error. A relay log can contain a
partial GTID transaction when AUTO_POSITION
is enabled if a receiver thread is restarted when it is in the
middle of transferring a transaction from a master. On restart
the slave retrieves the full transaction again. In this case,
the first relay log contains a partial GTID transaction and the
second relay log contains the full GTID transaction again. When
using mysqlbinlog to concatenate such a relay
log, the partial transaction was not being correctly detected
and therefore a ROLLBACK
was not being
correctly generated. The fix identifies partial GTID
transactions using the format description event of the second
relay log, ensuring that a ROLLBACK
is
correctly added.
(Bug #70711, Bug #17650326)
For small values of the
read_rnd_buffer_size
system
variable, internal caching of temporary results could fail and
cause query execution failure.
(Bug #20895852)
The normalize_statement()
UDF used by MySQL Enterprise Firewall
could cause a server exit for certain password-related
statements.
(Bug #20873209)
A failed FLUSH PRIVILEGES
statement followed by statements to create or drop accounts
could cause a server exit.
(Bug #20857652)
MySQL Enterprise Firewall debug code could leak memory. (Bug #20849157)
std::stringstream
code used by MySQL Enterprise Firewall could
cause a server exit.
(Bug #20848536)
SHOW VARIABLES
mutexes were being
locked twice, resulting in a server exit.
(Bug #20788853)
ull2dec()
was modified to avoid a problem
with GCC 5 in optimized mode.
(Bug #20768820)
Using GCC 5, debug builds failed due to compiler warnings. (Bug #20768717)
The
mysql_firewall_max_query_size
system variable should be read only at runtime, but it was
possible to modify it.
(Bug #20608993)
MySQL Enterprise Firewall could leak memory in the unlikely event of failure to
store information in an INFORMATION_SCHEMA
table.
(Bug #20593257)
Under certain conditions, the libedit
command-line library could write outside an array boundary and
cause a client program crash.
(Bug #20318154)
mysql_config_editor could exit abnormally while encrypting passwords. (Bug #20294225)
Host value matching for the grant tables could fail to use the most specific of values that contained wildcard characters. (Bug #20181776)
For MySQL distributions linked against yaSSL, a corrupt client key file could cause clients to exit. (Bug #20168526)
For join queries with a large number of tables, the server could exit converting the join to a semijoin. (Bug #20109861)
Deleting rows from mysql.user
following by
granting privileges to a new account could result in a server
exit.
(Bug #20031475)
Renaming the mysql.procs_priv
table and
executing SHOW GRANTS
resulted in
a server exit.
(Bug #20006361)
Within a stored procedure, access to view columns after DDL or
FLUSH TABLES
statements in the
procedure could cause a server exit.
(Bug #19897405)
Execution of certain BINLOG
statements while temporary tables were open by
HANDLER
statements could cause a
server exit.
(Bug #19894987, Bug #20449914)
For a prepared statement with an ORDER BY
that refers by column number to a
GROUP_CONCAT()
expression that
has an outer reference, repeated statement execution could cause
a server exit.
(Bug #19814337)
CMake configuration was adjusted to handle
new warnings reported by Clang 3.5, using the
-Wpointer-bool-conversion
and
-Wundefined-bool-conversion
compiler options.
(Bug #19584183)
Loading corrupt spatial data into a MyISAM
table could cause the server to exit during index building.
(Bug #19573096)
Specifying --general_log_file=
(with an empty value) at server startup caused the server to
fail and exit.
(Bug #19392264)
CMake configuration was adjusted to handle warnings reported by Clang 3.3. (Bug #17486216)
Some MySQL Enterprise Firewall diagnostic messages were written outside the control
of the log_error_verbosity
system variable.
(Bug #76612, Bug #20848331)
The server rejected empty COM_SHUTDOWN
packets.
(Bug #76552, Bug #20810928)
References: This issue is a regression of: Bug #14525642.
A Provides
rule in RPM
.spec
files misspelled
“mysql-embedded” as “mysql-emdedded”.
(Bug #76385, Bug #20734434)
Inappropriate -Werror
options could appear in
mysql_config --cflags output.
(Bug #76019, Bug #20590904)
Using a MySQL 5.6 version of mysqladmin to change the password for an account on a MySQL 5.7.6 installation resulted in an unusable account password. (Bug #76018, Bug #20590548)
AddressSanitizer compilation errors were silenced. (Bug #75739, Bug #20459338, Bug #75740, Bug #20459363)
In the threads
Performance Schema
table, the PROCESSLIST_STATE
and
PROCESSLIST_INFO
values did not change for
the thread/sql/main
main thread instrument as
the thread state changed.
(Bug #74517, Bug #19887143)
Certain queries for the INFORMATION_SCHEMA
TABLES
and
COLUMNS
tables could lead to
excessive memory use when there were large numbers of empty
InnoDB
tables.
(Bug #72322, Bug #18592390)
Queries that included a HAVING
clause based
on nondeterministic functions could produce incorrect results.
(Bug #69638, Bug #17055185)
For logging of prepared statements to the general query log, the
Execute
line was logged after statement
execution, not before.
(Bug #69453, Bug #16953758, Bug #20536590)
MySQL failed to compile using OpenSSL 0.9.8e. (Bug #68999, Bug #16861371)