abacker@antoo-laptop:/var/www/wp$ mysql -u root -p -D mysql
Enter password:
Reading table information for completion of table and column names
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Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 88
Server version: 5.1.54-1ubuntu4 (Ubuntu)

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This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL v2 license

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

mysql> SELECT host, user, password FROM user WHERE user = 'wordpress';
+------+-----------+-------------------------------------------+
| host | user      | password                                  |
+------+-----------+-------------------------------------------+
| %    | wordpress | *F33AE6DD04EF4C7C1D3105568E7FB7C1EE16C937 |
+------+-----------+-------------------------------------------+
1 row in set (0.00 sec)

mysql> SET PASSWORD FOR wordpress = PASSWORD('a');
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT host, user, password FROM user WHERE user = 'wordpress';
+------+-----------+-------------------------------------------+
| host | user      | password                                  |
+------+-----------+-------------------------------------------+
| %    | wordpress | *667F407DE7C6AD07358FA38DAED7828A72014B4E |
+------+-----------+-------------------------------------------+
1 row in set (0.00 sec)

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> \q
Bye
/var/www/wp$ mysql -u wordpress -pa
ERROR 1045 (28000): Access denied for user 'wordpress'@'localhost' (using password: YES)