As an alternative approach, if you want to avoid that voodo, you could read your db data into a hash using open. This would also replace all your separate (but related) scalar variables with a single hash variable.

$ cat dbconnect.txt
# set up the database connection variables
username    = foo
password    = somepassword
host        = localhost
database    = adb
table       = notactual
$
$ cat ./770979.pl
#!/usr/bin/env perl

use strict;
use warnings;
use Data::Dumper;

my %db_data;
my $file = 'dbconnect.txt';
open my $fh, '<', $file or die "Can not open file $file: $!";
while (<$fh>) {
    chomp;
    next if /\s*#/;     # Ignore comments
    if (/=/) {
        my ($k, $v) = split /\s*=\s*/;
        $db_data{$k} = $v;
    }
}
close $fh;
print Dumper(\%db_data);

$ ./770979.pl
$VAR1 = {
          'database' => 'adb',
          'password' => 'somepassword',
          'table' => 'notactual',
          'host' => 'localhost',
          'username' => 'foo'
        };
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Yet another alternative approach is to use one of the CPAN modules, such as Config::Simple.