Changes in MySQL 8.4.7 (2025-10-21, LTS Release)

• Audit Log Notes

• Compilation Notes

• SQL Function and Operator Notes

• InnoDB Notes

• Optimizer Notes

• Packaging Notes

• Performance Schema Notes

• Bugs Fixed

Audit Log Notes

• Fixed an issue related to audit log strategy. (Bug #38223011)

• Improved performance related to adding multiple general_sql_command.str fields to an Enterprise Audit filter. (Bug #38053242)

• Fixed an issue related to audit_log_read performance. (Bug #36281295, Bug #38275868)

Compilation Notes

• OpenSSL 3 is now used on Solaris. (Bug #38193362)

• Upgraded the bundled googletest library to version 1.17. (Bug #38152017)

• Upgraded the bundled libbacktrace library to the latest version (April 2025). (Bug #38151970)

• Warnings raised by Clang 20 for non-trivially copyable types, deprecated literal operators, and incorrect main function declarations are no longer generated. (Bug #37785251)

SQL Function and Operator Notes

• Fixed an issue related to executing certain UPDATE statements. (Bug #37590580)

  References: This issue is a regression of: Bug #31562881.

InnoDB Notes

• Creating a thread for parallel scan may fail, resulting in assertion failures when it fell back to single-thread mode. Errors were returned similar to the following:

          Assertion failure: row0pread.h:306:active >= n_threads

  (Bug #38325137)

• Under certain circumstances, a virtual index rollback could fail on 32-bit builds of MySQL Server. (Bug #38167527)

• If the buffer pool was very large, it could lead to a large number of chunks required by each buffer pool instance, which could fail if the operating system was unable to allocate the required memory.

  As of this release, this allocation is checked to ensure it is allocated correctly. (Bug #37994397)

• Fixed an issue relating to modifying the internal FTS configuration. (Bug #37792010)

• Fixed an issue related to virtual indexes. (Bug #37602657)

• If the row size exceeded the maximum allowed size due to innodb_strict_mode=OFF, confusing warning messages similar to "Cannot add field" could appear in certain situations, such as selecting from a table or dropping a column.

  Error messages are improved for this scenario. (Bug #37003342, Bug #36768046, Bug #36867372)

Optimizer Notes

• Fixed an issue relating to SQL queries involving correlated scalar subqueries and JSON tables. (Bug #36684370)

Packaging Notes

• For platforms on which OpenSSL libraries are bundled, the linked OpenSSL library for MySQL Server has been updated to version 3.0.17. For more information, see OpenSSL 3.0 Series Release Notes. (Bug #38457056)

• MySQL Server RPM installation on Fedora 42 could fail due to conflicts with MariaDB 11.8 packages. Errors were returned similar to the following:

          file /usr/bin/mysqld conflicts between mysql-community-server-8.4.7
          and mariadb11.8-server-3:11.8.3, file
          /usr/share/man/man1/mysql.1.gz conflicts between mysql-community-
          client-8.4.7 and mariadb11.8, file
          /usr/lib/systemd/system/mysqld.service conflicts between mysql-
          community-server-8.4.7 and mariadb11.8-server

  (Bug #38384844)

Performance Schema Notes

• Connections waiting on the connection control plugin were not displayed in the performance_schema.processlist table. (Bug #38043683)

Bugs Fixed

• Logical clock handling for CREATE ... SELECT statements has been improved to ensure accurate logical clock values in the replica relay log. (Bug #38383106)

• The server sometimes processed table references incorrectly. (Bug #38001000)

• PARTITION BY ... (DEFAULT (column)) was not always handled correctly. (Bug #111234, Bug #35451459)

  References: This issue is a regression of: Bug #33142135.