1、错误信息
  截图：

Attaching to my_wordpress-db-1, my_wordpress-wordpress-1
my_wordpress-db-1         | 2022-09-25 07:57:05+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.27-1debian10 started.
my_wordpress-db-1         | 2022-09-25 07:57:06+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
my_wordpress-db-1         | 2022-09-25 07:57:06+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.27-1debian10 started.
my_wordpress-wordpress-1  | AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 172.19.0.2. Set the 'ServerName' directive globally to suppress this message
my_wordpress-wordpress-1  | AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 172.19.0.2. Set the 'ServerName' directive globally to suppress this message
my_wordpress-db-1         | 2022-09-25 07:57:06+00:00 [Note] [Entrypoint]: Initializing database files
my_wordpress-db-1         | 2022-09-25T07:57:06.492880Z 0 [Warning] [MY-010918] [Server] 'default_authentication_plugin' is deprecated and will be removed in a future release. Please use authentication_policy instead.
my_wordpress-db-1         | 2022-09-25T07:57:06.492911Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.27) initializing of server in progress as process 40
my_wordpress-db-1         | 2022-09-25T07:57:06.499967Z 0 [ERROR] [MY-010457] [Server] --initialize specified but the data directory has files in it. Aborting.
my_wordpress-db-1         | 2022-09-25T07:57:06.499989Z 0 [ERROR] [MY-013236] [Server] The designated data directory /var/lib/mysql/ is unusable. You can remove all files that the server added to it.
my_wordpress-db-1         | 2022-09-25T07:57:06.500122Z 0 [ERROR] [MY-010119] [Server] Aborting
my_wordpress-db-1         | 2022-09-25T07:57:06.500419Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.27)  MySQL Community Server - GPL.
my_wordpress-wordpress-1  | [Sun Sep 25 07:57:06.506845 2022] [mpm_prefork:notice] [pid 1] AH00163: Apache/2.4.51 (Debian) PHP/7.4.27 configured -- resuming normal operations
my_wordpress-wordpress-1  | [Sun Sep 25 07:57:06.506951 2022] [core:notice] [pid 1] AH00094: Command line: 'apache2 -D FOREGROUND'

2、原因

错误发生原因暂时不清楚，有见解的同学可以在评论区帮忙解惑一下，谢谢

3、解决办法

原本搭建WordPress用的是官方的yml，如下：

services:
  db:
    image: mysql:latest
    command: '--default-authentication-plugin=mysql_native_password'
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=somewordpress
      - MYSQL_DATABASE=wordpress
      - MYSQL_USER=wordpress
      - MYSQL_PASSWORD=wordpress
    expose:
      - 3306
      - 33060
  wordpress:
    image: wordpress:latest
    volumes:
      - wp_data:/var/www/html
    ports:
      - 80:80
    restart: always
    environment:
      - WORDPRESS_DB_HOST=db
      - WORDPRESS_DB_USER=wordpress
      - WORDPRESS_DB_PASSWORD=wordpress
      - WORDPRESS_DB_NAME=wordpress
volumes:
  db_data:
  wp_data:

后来我把yml改成如下，就不报错了（这是我的解决办法，可能不是每个人都适用，把db里的volumes里的db_data删掉，然后把路径补全，把最下面的volumes里的db_data删掉）

services:
  db:
    image: mysql:latest
    command:
      --default-authentication-plugin=mysql_native_password
    volumes:
      - /home/mysql/data:/var/lib/mysql
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=somewordpress
      - MYSQL_DATABASE=wordpress
      - MYSQL_USER=wordpress
      - MYSQL_PASSWORD=wordpress
    expose:
      - 3306
      - 33060
  wordpress:
    image: wordpress:latest
    volumes:
      - wp_data:/var/www/html
    ports:
      - 80:80
    restart: always
    environment:
      - WORDPRESS_DB_HOST=db
      - WORDPRESS_DB_USER=wordpress
      - WORDPRESS_DB_PASSWORD=wordpress
      - WORDPRESS_DB_NAME=wordpress
volumes:
  wp_data: