this information is important to all answers above : When you restart mysql server all policy config will be RESET and will be LOST, so to make your policy configuration PERSISTENT, you should follow these instructions: (tested on ubuntu server version 20.10)

用mysql应用这些变化后，洪阮回答 Sudo nano /etc/mysql/mysql.conf.d/mysqld.cnf 加上最后一行:

[mysqld]
#
# * Basic Settings
#
..
..
..
validate_password.policy = LOW   # <== this line
..
..
# IMPORTANT notes: 
# - you can add more policy commands each by your needs.
# - notice the "." before "policy" , in some mysql versions is "_" , so be aware of that.

保存文件并重新启动mysql server: sudo service mysql restart 连接并检查配置的持久性: Sudo mysql -u your_username -p 显示像"validate_pass%"这样的变量; 结果应该是这样的:

+--------------------------------------+-------+
| Variable_name                        | Value |
+--------------------------------------+-------+
| validate_password.check_user_name    | ON    |
| validate_password.dictionary_file    |       |
| validate_password.length             | 6     |
| validate_password.mixed_case_count   | 1     |
| validate_password.number_count       | 0     |
| validate_password.policy             | LOW   |
| validate_password.special_char_count | 1     |
+--------------------------------------+-------+

我希望这能帮助到人们。

编辑:感谢@ahmednawazbutt:不要忘记FLUSH特权;

因为你的密码。你可以在MySQL客户端中使用以下查询查看密码验证配置指标:

SHOW VARIABLES LIKE 'validate_password%';

输出应该是这样的:

+--------------------------------------+-------+
| Variable_name                        | Value |
+--------------------------------------+-------+
| validate_password.check_user_name    | ON    |
| validate_password.dictionary_file    |       |
| validate_password.length             | 6     |
| validate_password.mixed_case_count   | 1     |
| validate_password.number_count       | 1     |
| validate_password.policy             | LOW   |
| validate_password.special_char_count | 1     |
+--------------------------------------+-------+

然后可以将密码策略级别设置低一些，例如:

SET GLOBAL validate_password.length = 6;
SET GLOBAL validate_password.number_count = 0;

查看MySQL文档。

注意:这可能不是一个安全的解决方案。但是如果您正在测试环境中工作，只需要快速修复，甚至不关心安全设置。这是一个快速的解决方案。

当我运行“mysql_secure_installation”并将密码安全级别修改为“中等”时，同样的问题发生在我身上。

我通过运行以下程序绕过了这个错误:

mysql -h localhost -u root -p
mysql>uninstall plugin validate_password;

如果需要，请确保重新安装插件“validate_password”。

对于Laravel用户在MySQL 8.0中遇到此问题。x,添加

'modes'=> [
             'ONLY_FULL_GROUP_BY',
             'STRICT_TRANS_TABLES',
             'NO_ZERO_IN_DATE',
             'NO_ZERO_DATE',
             'ERROR_FOR_DIVISION_BY_ZERO',
             'NO_ENGINE_SUBSTITUTION',
            ],

到你的database.php文件如下所示:

// database.php

    'connections' => [

        'mysql' => [
            'driver'      => 'mysql',
            'host'        => env( 'DB_HOST', '127.0.0.1' ),
            'port'        => env( 'DB_PORT', '3306' ),
            'database'    => env( 'DB_DATABASE', 'forge' ),
            'username'    => env( 'DB_USERNAME', 'forge' ),
            'password'    => env( 'DB_PASSWORD', '' ),
            'unix_socket' => env( 'DB_SOCKET', '' ),
            'charset'     => 'utf8mb4',
            'collation'   => 'utf8mb4_unicode_ci',
            'prefix'      => '',
            'strict'      => true,
            'engine'      => null,
            'modes'       => [
                'ONLY_FULL_GROUP_BY',
                'STRICT_TRANS_TABLES',
                'NO_ZERO_IN_DATE',
                'NO_ZERO_DATE',
                'ERROR_FOR_DIVISION_BY_ZERO',
                'NO_ENGINE_SUBSTITUTION',
            ],
        ],
    ],

它帮我解决了问题。

mysql> SET GLOBAL validate_password.policy = 0;

MySQL 8*

SET GLOBAL validate_password.policy=LOW

参考链接解释政策-点击这里