mysql> create user 'test1'@'localhost' identified by '123456';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

原因：密码策略问题

解决办法：
1.查看mysql初始的密码策略
mysql> show variables like 'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password_check_user_name    | OFF    |
| validate_password_dictionary_file    |        |
| validate_password_length             | 8      |
| validate_password_mixed_case_count   | 1      |
| validate_password_number_count       | 1      |
| validate_password_policy             | MEDIUM |
| validate_password_special_char_count | 1      |
+--------------------------------------+--------+
7 rows in set (0.04 sec)

2.设置密码的验证强度等级，设置validate_password_policy的全局参数为LOW
（修改为low后，就只验证密码的长度）
set global validate_password_policy=LOW;

mysql> show variables like 'validate_password%';
+--------------------------------------+-------+
| Variable_name                        | Value |
+--------------------------------------+-------+
| validate_password_check_user_name    | OFF   |
| validate_password_dictionary_file    |       |
| validate_password_length             | 8     |
| validate_password_mixed_case_count   | 1     |
| validate_password_number_count       | 1     |
| validate_password_policy             | LOW   |
| validate_password_special_char_count | 1     |
+--------------------------------------+-------+
7 rows in set (0.00 sec)

3.修改密码长度
set global validate_password_length=6;

mysql> show variables like 'validate_password%';
+--------------------------------------+-------+
| Variable_name                        | Value |
+--------------------------------------+-------+
| validate_password_check_user_name    | OFF   |
| 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     |
+--------------------------------------+-------+
7 rows in set (0.01 sec)

4.验证
mysql> create user 'test1'@'localhost' identified by '123456';
Query OK, 0 rows affected (0.06 sec)