"ERROR 1044 (42000) at line 39: Access denied for user 'drupal_user'@'localhost' to database 'mydb'"

$local_sites = '/Users/steve/Sites/';
$aliases['local'] = array(
  'uri' => 'default',
  'root' => $local_sites . 'mysite/public_html',
  'path-aliases' => array(
    '%files' => $local_sites . 'mysite/public_html/sites/default/files',
    '%dump-dir' => '/Users/steve/Sites/mysite',
   ),
);

$aliases['prod'] = array(
  'uri' => 'default',
  'os' => 'Linux',
  'root' => '/cluster/www_system/www/www.mysite.org/current_build/public_html',
  'remote-host' => 'control.cphwf01.local',
  'remote-user' => 'sedwards',
  'path-aliases' => array(
    '%files' => 'sites/default/files',
    '%dump-dir' => '/scratch',
   ),
);

Calling system(mysql --database=mydb --host=localhost --user=drupal_user --password=mypass --silent < /Users/steve/Sites/mysite/mysiteLeW4G5);

mysql --database=mydb --host=localhost --user=drupal_user --password=mypass

GRANT ALL PRIVILEGES ON `myDB`.* TO 'mySQLuser'@'localhost' WITH GRANT OPTION

GRANT USAGE ON *.* TO 'mySQLuser'@'localhost' IDENTIFIED BY PASSWORD 'pwd'

$aliases['local'] = array(   'uri' => 'http://yoursite.local',   'root' => $local_sites . 'all/themes/yourtheme/',   'path-aliases' => array(
    '%dump-dir' => $local_sites . 'all/drush/dbdumps',
    '%files' => 'sites/default/files',   ),   'databases' => array(
    'default' =>
      array(
        'default' =>
          array(
            'database' => 'db_name',
            'username' => 'user',
            'password' => 'pass',
            'host' => '127.0.0.1',
            'port' => '',
            'driver' => 'mysql',
            'prefix' => '',
          ),
      ),   ), );