Do you have any suggestions for perl-ish ways to tackle this?

My first thought is not to use Perl to do this, as you have said you are using a database.

Substitute the * wildcard characters for _ SQL wildcard characters and feed that directly into your SQL query.

my $search = 'D7*D';
$search =~ /*/_/g;
my ($id, $new) = $dbh->selectrow_array("SELECT rowid, new FROM table W
+HERE old LIKE ?", undef, $search);
[download]

(untested)