ERROR 1396 (HY000): Operation RENAME USER failed for ' root ' @ '% '

To avoid security risks in MySQL, rename the default root user.

Using the Rename user command to modify the root username failed,

Hint Error: 1396 (HY000): Operation RENAME USER failed for ' root ' @ '% '

Modified successfully using the User table under Update MySQL user.

mysql> use MySQL;

Database changed

Mysql> Select Host, user, password from user;

+-----------+------+-------------------------------------------+

| Host | user | password |

+-----------+------+-------------------------------------------+

| localhost | Root | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

| 127.0.0.1 | Root | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

| :: 1 | Root | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

+-----------+------+-------------------------------------------+

3 Rows in Set (0.00 sec)

mysql> Rename user root to admin;

ERROR 1396 (HY000): Operation RENAME USER failed for ' root ' @ '% '

However, it is no problem to rename a normal user with the same command.

mysql> Update user set user= ' admin ' where user= ' root ';

Query OK, 3 rows affected (0.09 sec)

Rows Matched:3 Changed:3 warnings:0

mysql> flush Privileges;

Query OK, 0 rows Affected (0.00 sec)

Mysql> Select Host, user, password from user;

+-----------+-------+-------------------------------------------+

| Host | user | password |

+-----------+-------+-------------------------------------------+

| localhost | admin | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

| 127.0.0.1 | admin | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

| :: 1 | admin | *81f5e21e35407d884a6cd4a731aebfb6af209e1b |

+-----------+-------+-------------------------------------------+

3 Rows in Set (0.00 sec)