mysql -u root -p

CREATE USER 'bill'@'%' IDENTIFIED BY 'passpass';

grant all privileges on *.* to 'bill'@'%' with grant option;

mysql -u bill -p

''@'localhost'

'bill'@'%'

'bill'@'%'

~$ mysql -u root -p
Enter Password:

mysql> grant all privileges on *.* to bill@localhost identified by 'pass' with grant option;

mysql -u bill -p

ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)

CREATE USER bill@localhost IDENTIFIED BY 'passpass';
grant all privileges on *.* to bill@localhost with grant option;

mysql -u bill -p -hmydb@mydomain.com
mysql -u bill -p -h10.1.2.30
mysql -u bill -p -h127.0.0.1 --protocol=TCP

SELECT USER(),CURRENT_USER();

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
| lwdba   | %         |
| mywife  | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
7 rows in set (0.00 sec)

mysql> grant all on *.* to x@'%';
Query OK, 0 rows affected (0.02 sec)

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
| lwdba   | %         |
| mywife  | %         |
| x       | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
8 rows in set (0.00 sec)

mysql> update mysql.user set user='' where user='x';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
|         | %         |
| lwdba   | %         |
| mywife  | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
8 rows in set (0.00 sec)

mysql>

C:MySQL_5.5.12>mysql -urol -Dtest -h127.0.0.1 --protocol=TCP
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 12
Server version: 5.5.12-log MySQL Community Server (GPL)

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

mysql> select user(),current_user();
+---------------+----------------+
| user()        | current_user() |
+---------------+----------------+
| rol@localhost | @%             |
+---------------+----------------+
1 row in set (0.00 sec)

mysql>

mysql -u mike -p mypass

mysql -u mike -pmypass

[client]
user = myusername
password = "mypassword"   # <----------------------- VERY IMPORTANT (quotes)
host = localhost

ERROR 1045 (28000): Access denied for user 'sonar'@'localhost' (using password: YES)

alm-lt-test.xyz.com

mysql -u sonar -p -halm-lt-test.xyz.com
mysql -u sonar -p -h101.33.65.94
mysql -u sonar -p -h127.0.0.1 --protocol=TCP
mysql -u sonar -p -h172.27.59.54 --protocol=TCP

GRANT ALL ON sonar.* TO 'sonar'@'localhost' IDENTIFIED BY 'sonar';
GRANT ALL ON sonar.* TO 'sonar'@'alm-lt-test.xyz.com' IDENTIFIED BY 'sonar';
GRANT ALL ON sonar.* TO 'sonar'@'127.0.0.1' IDENTIFIED BY 'sonar';
GRANT ALL ON sonar.* TO 'sonar'@'172.27.59.54' IDENTIFIED BY 'sonar';

bind-address = 127.0.0.1

mysql -u debian-sys-maint -p

SQL SECURITY DEFINER

SQL SECURITY INVOKER

CREATE USER 'bill'@'%' IDENTIFIED BY 'passpass';

CREATE USER 'bill'@'localhost' IDENTIFIED BY 'passpass';

mysql> select user,host from mysql.user;
+---------------+----------------------------+
| user          | host                       |
+---------------+----------------------------+
| bill          | %                          | <=== created by first
| root          | 127.0.0.1                  |
| root          | ::1                        |
| root          | localhost                  |
| bill          | localhost                  | <=== created by second
+---------------+----------------------------+

mysql -u bill -p

ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)

CREATE USER 'bill'@'localhost' IDENTIFIED BY 'passpass';

grant all privileges on . to 'bill'@'localhost' with grant option;

$ mysql -usomeuser -p's0mep@$$w0Rd'

$ mysql -usomeuser -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 191
Server version: 5.5.46-0ubuntu0.14.04.2 (Ubuntu)

Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

mysql>

UPDATE user SET plugin='mysql_native_password' WHERE user='foo';
FLUSH PRIVILEGES;

FLUSH PRIVILEGES;
CREATE USER bill@localhost IDENTIFIED BY 'passpass';
grant all privileges on *.* to bill@localhost with grant option;
FLUSH PRIVILEGES;

UPDATE mysql.user SET user='xxxx', password=PASSWORD('xxxx') WHERE user='';
FLUSH PRIVILEGES;