由于wordpress程序设计机制的问题：
我们在升级Wordpress时，Wordpress会在数据库wp_options表中增加core_updater.lock记录。
如中途打断Wordpress升级，这个记录会留在数据库中。
当下次升级时，Wordpress检测到此记录的存在就会返回”另一更新正在进行。
解决办法：登入Wordpress 数据库，删除 wp_options 表内 core_updater.lock
magth@iZ2zefqeda2588zscdjwkqZ:~/www$ mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 254
Server version: 8.0.26-0ubuntu0.20.04.2 (Ubuntu)
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Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> use wordpress;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from wp_options where option_name='core_updater.lock';
+-----------+-------------------+--------------+----------+
| option_id | option_name | option_value | autoload |
+-----------+-------------------+--------------+----------+
| 73243 | core_updater.lock | 1631777703 | no |
+-----------+-------------------+--------------+----------+
1 row in set (0.00 sec)
mysql> delete from wp_options where option_name='core_updater.lock';
Query OK, 0 rows affected (0.00 sec)
mysql>