#!/usr/bin/perl -T

# You do have taint mode turned on, don't you? and the next two lines, too?

use strict; 
use warnings;

my $cgi_obj = new CGI;

my $page = $cgi_obj->header( 'text/html' );
$page .= display( $cgi_obj );

print $page;

sub display
{
    my ( $query ) = @_;
    my $html = qq~
... (initial boilerplate stuff for the page) ...
~
    # run your dbi queries...
    # append more html stuff to $html as you go, and finally:

    $html .= qq~
</body>
</html>~;

    return $html;
}