在本地计算机上，我可以使用mysql cli命令轻松连接到mysql数据库的远程示例（假设设置了环境变量）：

# mysql -u root -p$DB_PASSWORD -h $DB_HOST --port=$DB_PORT

mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7365
Server version: 5.7.14-google (Google)

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owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
3 rows in set (0.05 sec)

但是，使用docker它只是挂起：

docker run --rm -it --name mysql -e MYSQL_RANDOM_ROOT_PASSWORD=yes mysql \
mysql -u root -p$DB_PASSWORD -h $DB_HOST --port=$DB_PORT

mysql: [Warning] Using a password on the command line interface can be insecure.
show databases;
^C
^C
exit
exit
^C

而且必须 docker container stop mysql 从另一个终端窗口退出mysql容器。
我甚至尝试连接到容器并运行相同的命令都没有用。尝试连接到一个aws mysql示例和google cloud sql示例，也尝试直接在命令行中输入变量，结果都是一样的。为什么要挂起来？我怎样才能让它工作？谢谢！