MySQL 5.7 Release Notes
The myisam_repair_threads
system variable and myisamchk
--parallel-recover
option are
deprecated; expect support for both to be removed in a future
release of MySQL.
Values other than 1 (the default) for
myisam_repair_threads
produce a
warning.
(WL #14937)
When the mysql client was started with
--default-character-set=utf8mb4
,
successive calls to the UUID()
function returned duplicate values.
(Bug #33334507)
References: See also: Bug #26395601, Bug #32224507.
The linked OpenSSL library for MySQL Server has been updated to version 1.1.1n from 1.1.1l. Issues fixed in OpenSSL are described at https://www.openssl.org/news/cl111.txt and at http://www.openssl.org/news/vulnerabilities.html. (Bug #33840722, Bug #33970835)
Group Replication:
The default for the
group_replication_transaction_size_limit
system variable, which sets the maximum transaction size that a
replication group accepts, is changed from zero (no limit) to
150000000 bytes (approximately 143 MB), which is the same as the
default in MySQL 8.0. Setting a limit for this system variable
by default helps to avoid delays or errors caused by excessively
large transactions. Transactions above the limit are rolled
back, and are not sent to the Group Communication System (GCS)
for distribution to the group. If your Group Replication servers
previously accepted transactions larger than the new default
limit, and you were allowing
group_replication_transaction_size_limit
to
default to the old zero limit, those transactions will start to
fail after the upgrade to the new default. You must either
specify an appropriate size limit that allows the maximum
message size you need the group to tolerate (which is the
recommended solution), or specify a zero setting to restore the
previous behavior.
(WL #15060)
InnoDB: A missing null pointer check for an index instance caused a failure. (Bug #33600109)
InnoDB: Purge threads processed undo records of an encrypted table for which the tablespace was not loaded, causing a failure. (Bug #32586721)
InnoDB:
Incorrect AUTO_INCREMENT
values were
generated when the maximum integer column value was exceeded.
The error was due to the maximum column value not being
considered. The previous valid AUTO_INCREMENT
value should have been returned in this case, causing a
duplicate key error.
(Bug #87926, Bug #26906787)
Partitioning:
In some cases, establishing a connection to MySQL server could
fail if the .ibd
file for a partition was
missing.
(Bug #33459653)
Statements that cannot be parsed (due, for example, to syntax errors) are no longer written to the slow query log. (Bug #33732907)
It was not possible to revoke the
DROP
privilege on the Performance
Schema.
(Bug #33578113)
A page cleaner thread timed out as it waited for an exclusive lock on an index page held by a full-text index creation operation on a large table. (Bug #33101844)
A memory leak occurred if mysqldump was used
on more than one table with the
--order-by-primary
option. The memory
allocated for sorting each table’s rows is now freed after
every table, rather than only once.
(Bug #30042589, Bug #96178)
mysqld_safe log message textual errors were corrected. Thanks to Bin Wang at China Mobile for the contribution. (Bug #106590, Bug #33903639)