DBD::CSV is definitely the way to go: 
use strict;
use DBI;

my $dbh = DBI->connect(
   "DBI:CSV:f_dir=.;csv_eol=\n;csv_sep_char=!;",
   {RaiseError=>1},
);

$dbh->{csv_tables}->{'class'} = { 
   file      => 'class.csv',
   col_names => [qw(id name class instructor)],
};

my $sth = $dbh->selectcol_arrayref("
   select distinct instructor
   from class
");

print join("\n",@$sth),"\n";

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: building Drop down menu - from a flat file by jeffa
in thread building Drop down menu - from a flat file by data67

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