MariaDB 10.4.9 发布了，值得关注的改进内容包括：
MDEV-20864: Debug-only option innodb_change_buffer_dump for dumping the contents of the InnoDB change buffer to the server error log at startup.
MariaBackup:
MDEV-18438: mbstream recreates xtrabackup_info on same direcTory as backup file
MDEV-20703: mariabackup creates binlog files in server binlog directory on --prepare --export step
FULLTEXT INDEX:
MDEV-19647: 删除全文索引并重启导致服务器挂起
MDEV-19529: InnoDB hang on DROP FULLTEXT INDEX
MDEV-19073: FTS row mismatch after crash recovery
MDEV-20621: FULLTEXT INDEX activity causes InnoDB hang
MDEV-20927: Duplicate key with auto increment
ALTER TABLE:
MDEV-20799: DROP Virtual Column crash
MDEV-20852: BtrBulk is unnecessarily holding dict_index_t::lock
System-Versioned Tables:
MDEV-16210: FK constraints on versioned tables use historical rows, which may cause constraint violation
MDEV-20812: Unexpected ER_ROW_IS_REFERENCED_2 or server crash in row_ins_foreign_report_err upon DELETE from versioned table with FK
MDEV-20117: corruption after instant DROP/reorder COLUMN
Galera wsrep library 升级到 26.4.3
为 Ubuntu 19.10 Eoan 准备的发行包已经就绪
修复以下 安全漏洞：
CVE-2019-2974
CVE-2019-2938
完整的改进记录请看 https://mariadb.com/kb/en/mariadb-1049-changelog/
