MySQL 8.0.28 will be officially GA on January 18, 2022. This is a maintenance release. In addition to bug fixes, some functional enhancements and adjustments have been made in this release. The details are as follows: InnoDB supports online execution of "ALTER TABLE ... RENAME COLUMN" using "ALGORITHM=INSTANT".
The "innodb_open_files" variable used to define the number of files that InnoDB can open at one time is now supported using the SELECT innodb_set_open_files_limit(N) statement.
The functions FROM_UNIXTIME(), UNIX_TIMESTAMP(), and CONVERT_TZ() can handle 64-bit values, and FROM_UNIXTIME() has a maximum of 32536771199.999999 seconds, corresponding to '3001-01-18 23:59:59.999999' UTC. UNIX_TIMESTAMP() maximum value '3001-01-18 23:59:59.999999' UTC, corresponding to 32536771199.999999 seconds. CONVERT_TZ() performs timezone conversion above 2038, up to '3001-01-18 23:59:59.999999' UTC.
Added state variable "Global_connection_memory" to observe the total memory consumed by all user connections. By setting "connection_memory_limit", you can specify the resource consumption limit per user connection.
The AUDIT_ABORT_EXEMPT privilege allows a user's query to always be executed, preventing users with sufficient privileges from exploiting MySQL Enterprise Audit's erroneously creating an "abort" entry in the audit log filter, preventing themselves and other administrators from accessing the system.
When the system variable "read_only" is disabled, the server will automatically restart the event scheduler on demand.
When using prepared statements, DATE_ADD() and DATE_SUB() return DATETIME values even if YEAR, MONTH, or DAY are included in the calculation without the time part.
Downgrade & Remove Remove support for TLSv1 and TLSv1.1.
The ASCII shortcuts for latin1 and the UNICODE shortcuts for ucs2 are deprecated and will be removed in a future version of MySQL. Users can use CHARACTER SET instead.
Character set and collation ucs2, macroman, macce, dec, p8 will be downgraded and will be deleted in the future. Users can use utf8mb4 instead.
For more details, please visit the official website. https://blogs.oracle.com/mysql/post/announcing-january-2022-releases-featuring-mysql-8028
MySQL 8.0.28 于 2022 年 1 月 18 日正式 GA。这是一个维护版本，在这个版本里除了进行 Bug 修复，还进行了一些功能增强与调整。详细内容如下：
InnoDB 支持使用“ALGORITHM=INSTANT”在线执行“ALTER TABLE ... RENAME COLUMN”。
“innodb_open_files”变量用来定义 InnoDB 一次可以打开文件的数量，现在支持使用 SELECT innodb_set_open_files_limit(N) 语句设置。
函数 FROM_UNIXTIME(), UNIX_TIMESTAMP(), 和 CONVERT_TZ() 可以处理 64 位的值，FROM_UNIXTIME() 最大 32536771199.999999 seconds 秒，对应'3001-01-18 23:59:59.999999' UTC。UNIX_TIMESTAMP() 最大值'3001-01-18 23:59:59.999999' UTC,对应 32536771199.999999 秒。CONVERT_TZ() 执行 2038 以上的时区转换，最大'3001-01-18 23:59:59.999999' UTC.
增加状态变量“Global_connection_memory”用来观察所有用户连接所消耗的总内存。通过设置“connection_memory_limit”，可以指定每个用户连接的资源消耗限制。
AUDIT_ABORT_EXEMPT 权限允许用户的查询总是被执行，以防止具有充足权限的用户利用 MySQL Enterprise Audit 的错误地在审计日志筛选器中创建一个“abort”项，阻止自己和其他管理员访问系统。
当禁用系统变量“read_only”时，服务器会按需自动重启事件调度器。
使用预编译语句时，DATE_ADD() 和 DATE_SUB() 返回 DATETIME 值，即使计算中包含 YEAR, MONTH, 或 DAY 不包含时间部分。
降级&删除
删除对 TLSv1 和 TLSv1.1 的支持。
字符集 latin1 的快捷方式 ASCII 和 UNICODE 的快捷方式 ucs2 被弃用，MySQL 的未来版本中将删除它们。用户可以使用 CHARACTER SET 代替。
字符集及排序规则 ucs2、macroman、macce、dec、p8 将降级，未来将删除。用户可以使用 utf8mb4 代替。
更多详细内容可访问官网。https://blogs.oracle.com/mysql/post/announcing-january-2022-releases-featuring-mysql-8028
