@row_ary  = $sth->fetchrow_array; 
  $ary_ref  = $sth->fetchrow_arrayref; 
  $hash_ref = $sth->fetchrow_hashref;

	my $sth = $dbh->prepare ($query); 
	$sth->execute ();

while (my @row_ary = $sth->fetchrow_array ()) { 
  print $row_ary[0]; 
}

while (my $ary_ref = $sth->fetchrow_arrayref()) { 
  print $ary_ref->[0]; 
}

while (my $hash_ref = $sth->fetchrow_hashref ()) { 
  print $hash_ref->{key1}; 
}