Log Message:
mysql57: updated to 5.7.38

Changes in MySQL 5.7.38

SQL Function and Operator Notes

When the mysql client was started with --default-character-set=utf8mb4, \ 
successive calls to the UUID() function returned duplicate values.

Security Notes

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.

Functionality Added or Changed

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 \ 
Group Replication's 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.

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.

Bugs Fixed

InnoDB: A missing null pointer check for an index instance caused a failure.

InnoDB: Purge threads processed undo records of an encrypted table for which the \ 
tablespace was not loaded, causing a failure.

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.

Partitioning: In some cases, establishing a connection to MySQL server could \ 
fail if the .ibd file for a partition was missing.

Statements that cannot be parsed (due, for example, to syntax errors) are no \ 
longer written to the slow query log.

It was not possible to revoke the DROP privilege on the Performance Schema.

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.

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.

mysqld_safe log message textual errors were corrected.