MySQL Community Server 5.7.33 has been released
Posted by: Gipson Pulla
Date: January 18, 2021 07:41AM
Date: January 18, 2021 07:41AM
Dear MySQL users, MySQL Server 5.7.33, a new version of the popular Open Source Database Management System, has been released. MySQL 5.7.33 is recommended for use on production systems. For an overview of what's new in MySQL 5.7, please see http://dev.mysql.com/doc/refman/5.7/en/mysql-nutshell.html For information on installing MySQL 5.7.33 on new servers, please see the MySQL installation documentation at http://dev.mysql.com/doc/refman/5.7/en/installing.html MySQL Server 5.7.33 is available in source and binary form for a number of platforms from our download pages at http://dev.mysql.com/downloads/mysql/ MySQL Server 5.7.33 is also available from our repository for Linux platforms, go here for details: http://dev.mysql.com/downloads/repo/ Windows packages are available via the Installer for Windows or .ZIP (no-install) packages for more advanced needs. The point and click configuration wizards and all MySQL products are available in the unified Installer for Windows: http://dev.mysql.com/downloads/installer/ 5.7.33 also comes with a web installer as an alternative to the full installer. The web installer doesn't come bundled with any actual products and instead relies on download-on-demand to fetch only the products you choose to install. This makes the initial download much smaller but increases install time as the individual products will need to be downloaded. We welcome and appreciate your feedback, bug reports, bug fixes, patches, etc.: http://bugs.mysql.com/report.php The following link lists the changes in the MySQL 5.7 since the release of MySQL 5.7.32. It may also be viewed online at http://dev.mysql.com/doc/relnotes/mysql/5.7/en/news-5-7-33.html Enjoy! Changes in MySQL 5.7.33 (2021-01-18, General Availability) Optimizer Notes * MySQL attempts to use an ordered index for any ORDER BY or GROUP BY query that has a LIMIT clause, overriding any other choices made by the optimizer, whenever it determines that this would result in faster execution. Because the algorithm for making this determination makes certain assumptions about data distribution and other conditions, it may not always be completely correct, and it is possible in some cases that choosing a different optimization for such queries can provide better performance. To handle such occurrences, it is now possible to disable this optimization by setting the optimizer_switch system variable's prefer_ordering_index flag to off. For more information about this flag and examples of its use, see Switchable Optimizations https://dev.mysql.com/doc/refman/5.7/en/switchable-optimizations.html and LIMIT Query Optimization https://dev.mysql.com/doc/refman/5.7/en/limit-optimization.html Our thanks to Jeremy Cole for the contribution. (Bug #31686878) References: See also: Bug #97001, Bug #30348211. Security Notes * The linked OpenSSL library for MySQL Server has been updated to version 1.1.1i. Issues fixed in the new OpenSSL version are described at https://www.openssl.org/news/cl111.txt and https://www.openssl.org/news/vulnerabilities.html. (Bug #32260610) Functionality Added or Changed * When invoked with the --all-databases option, mysqldump now dumps the mysql database first, so that when the dump file is reloaded, any accounts named in the DEFINER clause of other objects will already have been created. (Bug #32141046) Bugs Fixed * InnoDB: The full-text search synchronization thread attempted to read a previously-freed word from the index cache. (Bug #31310404) * InnoDB: Calls to numa_all_nodes_ptr were replaced by the numa_get_mems_allowed() function. Thanks to Daniel Black for the contribution. (Bug #24693086, Bug #83044) * Replication: When the system variable transaction_write_set_extraction=XXHASH64 is set, which is the default in MySQL 8.0 and a requirement for Group Replication, the collection of writes for a transaction previously had no upper size limit. Now, for standard source to replica replication, the numeric limit on write sets specified by binlog_transaction_dependency_history_size is applied, after which the write set information is discarded but the transaction continues to execute. Because the write set information is then unavailable for the dependency calculation, the transaction is marked as non-concurrent, and is processed sequentially on the replica. For Group Replication, the process of extracting the writes from a transaction is required for conflict detection and certification on all group members, so the write set information cannot be discarded if the transaction is to complete. The byte limit set by group_replication_transaction_size_limit is applied instead of the numeric limit, and if the limit is exceeded, the transaction fails to execute. (Bug #32019842) * Replication: On a multi-threaded replica where the commit order is preserved, worker threads must wait for all transactions that occur earlier in the relay log to commit before committing their own transactions. If a deadlock occurs because a thread waiting to commit a transaction later in the commit order has locked rows needed by a transaction earlier in the commit order, a deadlock detection algorithm signals the waiting thread to roll back its transaction. Previously, if transaction retries were not available, the worker thread that rolled back its transaction would exit immediately without signalling other worker threads in the commit order, which could stall replication. A worker thread in this situation now waits for its turn to call the rollback function, which means it signals the other threads correctly. (Bug #26883680, Bug #87796) * Microsoft Windows: On Windows, running the MySQL server as a service caused shared-memory connections to fail. (Bug #32009251) * The server did not handle all cases of the WHERE_CONDITION optimization correctly. (Bug #31905199) * For the engines which support primary key extension, when the total key length exceeded MAX_KEY_LENGTH or the number of key parts exceeded MAX_REF_PARTS, key parts of primary keys which did not fit within these limits were not added to the secondary key, but key parts of primary keys were unconditionally marked as part of secondary keys. This led to a situation in which the secondary key was treated as a covering index, which meant sometimes the wrong access method was chosen. This is fixed by modifying the way in which key parts of primary keys are added to secondary keys so that those which do not fit within which do not fit within the limits mentioned previously mentioned are cleared. (Bug #31617858) * Privileges for some INFORMATION_SCHEMA tables were checked incorrectly. (Bug #31553323) * In certain cases, the server did not handle multiply-nested subqueries correctly. (Bug #31472704) * Certain accounts could cause server startup failure if the --skip-name-resolve option was enabled. (Bug #31018510) * Client programs could unexpectedly exit if communication packets contained bad data. (Bug #30890850) * A buffer overflow in the client library was fixed. (Bug #30885987) * mysql_config_editor incorrectly treated # in password values as a comment character. (Bug #29861961, Bug #95597) On Behalf of MySQL/ORACLE RE Team Gipson Pulla
Edited 1 time(s). Last edit at 01/18/2021 07:42AM by Gipson Pulla.
MySQL Community Server 5.7.33 has been released
January 18, 2021 07:41AM
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