my $sql = qq(select * from table order by id);

my $data_col = $dbh->selectcol_arrayref($sql, { Columns => [ 2, 3 ] });

my %seen;
my @list = @$data_col;

while (@list){
    my $line_n = shift @list;
    my $word = shift @list;
    
    if ($seen{$line_n}++) {
    	print " ";
    } else {
    	print "\n$line_n - ";
    }
    print $word;
}