DROP User 'netbeansuser'@'%'; throws Error HY000 (1396) MySQL

Question

I mistakenly created a user that I am unable to delete. Following is the code snippet interacting with MySQL:

mysql> DROP User 'netbeansuser'@'%';
ERROR 1396 (HY000): Operation DROP USER failed for 'netbeansuser'@'%'
mysql> select User from mysql.user;
+------------------+
| User             |
+------------------+
| root             |
| root             |
| debian-sys-maint |
| netbeansuser     |
| root             |
| root             |
+------------------+
6 rows in set (0.00 sec)

mysql> DROP User 'netbeansuser';
ERROR 1396 (HY000): Operation DROP USER failed for 'netbeansuser'@'%'
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> select User from mysql.user;
+------------------+
| User             |
+------------------+
| root             |
| root             |
| debian-sys-maint |
| netbeansuser     |
| root             |
| root             |
+------------------+
6 rows in set (0.00 sec) 

mysql> DROP User 'netbeansuser';
ERROR 1396 (HY000): Operation DROP USER failed for 'netbeansuser'@'%'
mysql> DROP User 'netbeansuser'@'%';
ERROR 1396 (HY000): Operation DROP USER failed for 'netbeansuser'@'%'

What am I doing wrong? Particularly, what is the '%' sign at the hostname for? I didn't specify the hostname while creating the user. Any resources on understanding hostname bindings in MySQL USER creation will also help. Thanks all.

Answer 1

I created the user john with the host localhost as shown below:

CREATE USER 'john'@'localhost';

But, I did not specify localhost to drop the user john as shown below:

DROP USER john;

Then, I got the error below:

ERROR 1396 (HY000): Operation DROP USER failed for 'john'@'%'

So, I specified localhost as shown below, then I could drop the user john without error:

DROP USER 'john'@'localhost';

Or:

DROP USER john@localhost;

Answer 2

This will be helpful.

Use 'localhost' instead of '%'.