perl -MDBI -we'my $dbh=DBI->connect("dbi:mysql:","","")'
DBI connect('','',...) failed: Access denied for user 'ben'@'localhost' (using password: NO) at -e line 1

##</code><code>##

mysql --user="" --password=""
ERROR 1045 (28000): Access denied for user 'ben'@'localhost' (using password: NO)