Using '' (or undef) works for me 
#!perl
use strict;
use DBI;
my $dbh = DBI->connect('DBI:mysql:test:localhost','','')
  or die $DBI::errstr;
print $dbh->tables;

[download]
poj

In reply to Re^5: Using DB->connect for mysql db without password by poj
in thread Using DB->connect for mysql db without password by angeloulivieri

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