Ubuntu 18.04.1 mysql password settings, and can be set without sudo login

Description:

After installing Ubuntu 18.04.1 , you cannot execute the mysql command as a user. You must use sudo to execute the mysql directive, and any php program may not be able to connect to mysql.

Step1: Login to the mysql interface

example:
Sudo mysql -uroot -p
Enter password: [press Enter directly]

Step2: Modify the account management mode and change password

mysql> Use mysql;

mysql> Update user SET plugin='mysql_native_password' WHERE User='root';

mysql> Update user set authentication_string=password('root new password') where user='root';

mysql> Flush privileges;

Step3: After logging out, you can use the following mysql command without adding sudo