A known limitation of this release:
If you have InnoDB
tables with full-text
search indexes and you are upgrading from MySQL 5.6.10 to a
MySQL version up to and including MySQL 5.6.18, the server
will fail to start after the upgrade (Bug#72079). This bug is
fixed in MySQL 5.6.19. As a workaround, remove full-text
search indexes prior to upgrading and rebuild full-text search
indexes after the upgrade is completed.
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MySQL 5.7 changed audit log file output to a new format that has better compatibility with Oracle Audit Vault. This format has been backported to MySQL 5.6 and it is possible to select either the old or new format using the new
audit_log_format
system variable, which has permitted values ofOLD
andNEW
(defaultOLD
). For details about each format, see Audit Log File Formats.In addition, when the audit log plugin rotates the audit log file, it uses a different file name format. For a log file named
audit.log
, the plugin previously renamed the file toaudit.log.
. The plugin now renames the file toTIMESTAMP
audit.log.
to indicate that it is an XML file.TIMESTAMP
.xmlIf you change the value of
audit_log_format
, use this procedure to avoid writing log entries in one format to an existing log file that contains entries in a different format:Stop the server.
Rename the current audit log file manually.
Restart the server with the new value of
audit_log_format
. The audit log plugin will create a new log file, which will contain log entries in the selected format.
The API for writing audit plugins has also changed. The
mysql_event_general
structure has new members to represent client host name and IP address, command class, and external user. For more information, see Writing Audit Plugins.
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Incompatible Change: In MySQL 5.6.13, the
statement/com/
abstract statement instrument in thesetup_instruments
Performance Schema table was renamed tostatement/com/new_packet
. That change has been reverted.Applications that refer to the old instrument name must be updated with the new name. For more information about the use of abstract instruments in statement classification, see Performance Schema Statement Event Tables. (Bug #16750433, Bug #17271055)
InnoDB: The
InnoDB
memcached plugin now supports inserts and reads on mappedInnoDB
tables that have anINTEGER
defined as the primary key. (Bug #17315083, Bug #17203937)
Important Change; Replication:
START SLAVE UNTIL SQL_AFTER_GTIDS
did not cause the slave to stop until the next GTID event was received following execution of the transaction having the indicated GTID, which could cause issues in the case when the next GTID event is delayed, or does not exist. Now the slave stops after completing the transaction with that GTID. (Bug #14767986)-
InnoDB; Partitioning: Following any query on the
INFORMATION_SCHEMA.PARTITIONS
table,InnoDB
index statistics as shown in the output of statements such asSELECT
* FROM
INFORMATION_SCHEMA.STATISTICS
were read from the last partition, instead of from the partition containing the greatest number of rows. (Bug #11766851, Bug #60071)References: See also: Bug #16882435, Bug #69179.
InnoDB: When logging the delete-marking of a record during online
ALTER TABLE...ADD PRIMARY KEY
,InnoDB
writes the transaction ID to the log as it was before the deletion or delete-marking of the record. When doing this,InnoDB
would overwrite theDB_TRX_ID
field in the original table, which could result in locking issues. (Bug #17316731)InnoDB: The
row_sel_sec_rec_is_for_clust_rec
function would incorrectly prepare to compare a NULL column prefix in a secondary index with a non-NULL column in a clustered index. (Bug #17312846)InnoDB: An assertion would be raised in
fil_node_open_file
due to a missing.ibd
file. Instead of asserting,InnoDB
should return false and the caller offil_node_open_file
should handle the return message. (Bug #17305626, Bug #70007)InnoDB: An incorrect purge would occur when rolling back an update to a delete-marked record. (Bug #17302896)
InnoDB: The assertion
ut_ad(oldest_lsn <= cur_lsn)
in filebuf0flu.cc
failed because the current max LSN would be retrieved from the buffer pool before the oldest LSN. (Bug #17252421)InnoDB:
InnoDB
memcachedadd
andset
operations would perform more slowly than SQLINSERT
operations. (Bug #17214191)InnoDB: As commented in
log0log.h
,old_lsn
andold_buf_free
should only be compiled whenUNIV_LOG_DEBUG
is enabled. (Bug #17160270, Bug #69724)InnoDB: Adding a foreign key with a constraint name that included the string “_ibfk_” caused
InnoDB
to create a duplicate constraint with a generated internal name. The generated internal name could also collide with an existing user-defined constraint of the same name, causing a duplicate key error. (Bug #17076737, Bug #69693, Bug #17076718, Bug #69707)InnoDB: The
ha_innobase::clone
function would incorrectly assert that a thread cannot clone a table handler that is used by another thread, and that the original table handler and the cloned table handler must belong to the same transaction. The incorrect assertions have been removed. (Bug #17001980)InnoDB: A regression introduced in the fix for Bug #14606334 would cause crashes on startup during crash recovery. (Bug #16996584)
InnoDB: Rolling back an
INSERT
after a failedBLOB
write would result in an assertion failure. The assertion has been modified to allow NULLBLOB
pointers if an error occurs during aBLOB
write. (Bug #16971045)InnoDB: When dropping all indexes on a column with multiple indexes,
InnoDB
failed to block aDROP INDEX
operation when a foreign key constraint requires an index. (Bug #16896810)InnoDB: An assertion failure would occur in file
row0log.cc
onROW_FORMAT=REDUNDANT
tables that contained an unexpected but valid data directory flag. (Bug #16863098)-
InnoDB: A regression introduced with the fix for Bug #11762038 would cause
InnoDB
to raise an incorrect error message. The message stated that, “InnoDB cannot delete/update rows with cascading foreign key constraints that exceed max depth of 20”. The error message would occur when killing connections reading fromInnoDB
tables that did not have foreign key constraints. (Bug #16710923)References: This issue is a regression of: Bug #11762038.
InnoDB: In debug builds, an assertion failure would occur if
innodb_log_group_home_dir
does not exist. Instead of an assertion,InnoDB
now aborts with an error message ifinnodb_log_group_home_dir
does not exist. (Bug #16691130, Bug #69000)InnoDB: For the Barracuda file format and beyond, the externally stored prefix would be read even though the prefix is already stored locally in memory. (Bug #16569640)
InnoDB: When changing the shared tablespace file name using
innodb_data_file_path
and leaving the current log files in place,InnoDB
would create a new tablespace file and overwrite the log files resulting in a mismatch between the data dictionary and tables on disk. This bug fix ensures thatInnoDB
does not create a new tablespace if there are inconsistent system tablespaces, undo tablespaces, or redo log files. (Bug #16418661)InnoDB: Persistent statistics would be disabled unnecessarily when running in read-only mode. When running in read-only mode, fetching statistics from disk does not involve any modification of on-disk data except for when
ANALYZE TABLE
is run. This fix enables persistent statistics for read-only mode. (Bug #16083211)InnoDB: The documentation incorrectly stated that
START TRANSACTION WITH CONSISTENT SNAPSHOT
provides a consistent snapshot only if the current isolation level isREPEATABLE READ
orSERIALIZABLE
.START TRANSACTION WITH CONSISTENT SNAPSHOT
only works withREPEATABLE READ
. All other isolation levels are ignored. The documentation has been revised and a warning is now generated whenever theWITH CONSISTENT SNAPSHOT
clause is ignored. (Bug #14017206, Bug #65146)InnoDB: The
srv_master_thread
background thread, which monitors server activity and performs activities such as page flushing when the server is inactive or in a shutdown state, runs on a one second delay loop.srv_master_thread
failed to check if the server is in a shutdown state before sleeping. (Bug #13417564, Bug #63276)InnoDB: An infinite loop could occur in
buf_page_get_gen
when handling compressed-only pages. (Bug #12560151, Bug #61132)Partitioning: Creating a table
t1
usingCREATE TABLE ... PARTITION BY LIST ... PARTITION ... VALUES IN (NULL)
, then attempting to executeCREATE TABLE ... LIKE t1
caused the server to fail. (Bug #16860588)Replication: The server attempted to perform an internal truncatation of the
slave_worker_info
table while resetting it, even though this is a DDL operation and should not be used conccurrently with DML operations. To prevent this from happening, the reset now performs sequential row deletion in place of the truncation operation. (Bug #17286858, Bug #69898)Replication: When the
--relay-log-info-file
option was used together withslave_parallel_workers
set to a value greater than 1, mysqld failed to start. (Bug #17160671)-
Replication: The commit error caused by the failure of binary log rotation failure generated an incident event in the binary log file and interrupted the user session with error messages which did not mention that the slave server would be stopped later when the incident event was replayed.
Now, when encountering binary log rotation failure, a more helpful error message is instead written to the log, alerting the user to investigate in a timely manner. (Bug #17016017)
Replication: It was possible in
CHANGE MASTER TO
statements to set theMASTER_DELAY
option greater than the supported maximum value (231 − 1
). In addition, the error resulting from settingMASTER_DELAY
to a value greater than232
was not handled correctly. (Bug #16820156, Bug #16960315, Bug #69249, Bug #69469)-
Replication: When a master with semisynchronous replication enabled was shut down, the master failed to wait for either a semisyncnronous
ACK
or timeout before completing the shutdown. This prevented semisynchronous replication from reverting to asynchronous replication and allowed open transactions to complete on the master, which resulted in missing events on the slave.To fix this problem, dump threads are now stopped last during shutdown, after the client is told to stop, so that, if the dump thread has pending events from active clients, they can be sent to the slave. (Bug #16775543)
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Replication: A session attachment error during group commit causes the rollback of the transaction (as intended), but the transaction in which this happened was still written to the binary log and replicated to the slave. Thus, such an error could lead to a mismatched master and slave.
Now when this error occurs, an incident event is written in the binary log which causes replication to stop, and notifies the user that redundant events may exist in the binary log. An additional error is also now reported to the client, indicating that the ongoing transaction has been rolled back. (Bug #16579083)
-
Replication:
START SLAVE
failed when the server was started withmaster_info_repository=TABLE
andrelay_log_info_repository=TABLE
and withautocommit=0
, together with--skip-slave-start
.A workaround for previous versions of MySQL is to restart the slave mysqld without the
--skip-slave-start
option. (Bug #16533802) Replication: A slave using row-based replication was unable to read the rows containing columns of type
MYSQL_TYPE_DECIMAL
properly (old-style decimal, used prior to MySQL 5.0.3). Now the slave throws an error if it receives this type of data. You can convert the old-styleDECIMAL
format to the binary format used in current MySQL releases withALTER TABLE
; see Upgrading from MySQL 4.1 to 5.0, for more information. (Bug #16416302)-
Replication:
DROP TEMP TABLE IF EXISTS
statements could lead to failures in applying the binary log during point-in-time recovery operations. This is due to the fact that, when using row-based replication, the server appendsIF EXISTS
to anyDROP TEMPORARY TABLE
statements written to the binary log, and that the slave SQL thread does not check * wildcard filter rules forDROP TEMPORARY TABLE IF EXISTS
. If--log-slave-updates
was also enabled on the slave, such a statement was preceded by aUSE
statement. If the database referred by theUSE
statement did not exist, the statement failed, and stopped replication.Now, when writing
DROP TEMPORARY TABLE IF EXISTS
into the binary log, noUSE
statement is written, and the table name in theDROP TEMPORARY TABLE
statement is a fully qualified table name. (Bug #16290902) -
Savepoints could not be used successfully following an
ER_LOCK_DEADLOCK
error (orER_LOCK_WAIT_TIMEOUT
error, ifinnodb_rollback_on_timeout
was enabled). (Bug #17356954)References: This issue is a regression of: Bug #14188793.
The
mysql_real_connect()
C API function could leak memory if it failed. (Bug #17337684)Full-text search on
InnoDB
tables failed on searches that used the+
boolean operator. (Bug #17280122)For single-threaded workloads, the optimizer recognizes some special cases for which it can avoid function calls and enhance performance. (Bug #17234723)
AES_ENCRYPT()
andAES_DECRYPT()
failed to work correctly when MySQL was built with anAES_KEY_LENGTH
value of 192 or 256. (Bug #17170207)SELECT * from performance_schema.events_statements_current
could raise an assertion due to a race condition under load. (Bug #17164720)InnoDB
full-text searches failed in databases whose names began with a digit. (Bug #17161372)A successful connection failed to reset the per-IP address counter used to count successive connection failures. This could possibly cause a host to be blocked, when the
max_connect_errors
limit was reached. (Bug #17156507)With the thread pool plugin enabled and SSL in use, an error in one connection might affect other connections, causing them to experience a lost connection. (Bug #17087862)
Under load, truncating the
accounts
Performance Schema table could cause a server exit. (Bug #17084615)Within a stored program, comparison of the value of a scalar subquery with an
IN
clause resulted in an error for the first execution and raised an assertion for the second execution. (Bug #17029399)The
my_strtoll10()
function could incorrectly convert some long string-format numbers to numeric values and fail to set the overflow flag. (Bug #16997513)A race condition in the thread pool plugin could cause status variables such as
Aborted_connects
not to be incremented and permitting concurrent kills to happen for the same thread ID. (Bug #16959022)-
For partitioned tables, queries could return different results depending on whether Index Merge was used. (Bug #16862316)
References: See also: Bug #17648468, Bug #176588348, Bug #18167648.
Excessive memory consumption was observed for multiple execution of a stored procedure under these circumstances: 1) The stored procedure had an SQL statement that failed during validation. 2) The stored procedure had an SQL statement that required repreparation. (Bug #16857395)
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For some statements, memory leaks could result when the optimizer removed unneeded subquery clauses. (Bug #16807641)
References: This issue is a regression of: Bug #15875919.
Password rewriting in the general query log now also applies to prepared statements. (Bug #16732621)
Within a stored procedure, repeated execution of a prepared
CREATE TABLE
statement for a table with partitions could cause a server exit. (Bug #16614004)-
For debug builds, when the optimizer removed an
Item_ref
pointing to a subquery, it caused a server exit. (Bug #16509874)References: This issue is a regression of: Bug #16318585.
If the primary key for the
mysql.proc
system table was removed (an unsupported and not-recommended operation), the server exited for subsequent stored procedure invocation. Similar problems could occur for other system tables. Now an error occurs instead. (Bug #16373054)Deadlocks involving metadata locks and
InnoDB
deadlocks were both reported as anER_LOCK_DEADLOCK
error, but onlyInnoDB
deadlocks rolled back the transaction. Now both deadlocks roll back the transaction. (Bug #14188793)Metadata returned for a prepared
SELECT
statement that had outer joins could indicate that columns containingNULL
values wereNOT NULL
. (Bug #12818811)For queries that accessed an
INFORMATION_SCHEMA
table in a subquery, an attempt to lock a mutex that had already been locked could cause a server crash. (Bug #11765744)-
Full-text search on
InnoDB
tables failed on searches for words containing apostrophes when using boolean operators.The
innodb_ft_max_token_size
maximum value was incorrectly defined as 252, which is the maximum byte length. The maximuminnodb_ft_max_token_size
value is now 84, which is the maximum character length. (Bug #69932, Bug #17276125) InnoDB
deadlock caused transaction rollback but did not release metadata locks, blocking concurrent DDL on the transaction tables until the connection that got the deadlock issued an explicitCOMMIT
orROLLBACK
. (Bug #69668, Bug #17054007)The
libmysql.dll
library was missing several symbols:my_init
,mysql_client_find_plugin
,mysql_client_register_plugin
,mysql_load_plugin
,mysql_load_plugin_v
,mysql_options4
, andmysql_plugin_options
. (Bug #69204, Bug #16797982, Bug #62394)mysqldump wrote
SET
statements asSET OPTION
, which failed when reloaded because the deprecatedOPTION
keyword has been removed fromSET
syntax. (Bug #67507, Bug #15844882)For failure to create a new thread for the event scheduler, event execution, or new connection, no message was written to the error log. This could lead to the impression that the event scheduler was running normally when it was not. (Bug #67191, Bug #14749800, Bug #16865959)
If one connection changed its default database and simultaneously another connection executed
SHOW PROCESSLIST
, the second connection could access invalid memory when attempting to display the first connection's default database. memory. (Bug #58198, Bug #11765252)For better robustness against stack overflow, the server now accounts for the size of the guard area when making thread stack size requests. (Bug #35019, Bug #11748074)