Sure, that's not bad. Generate image tags that are actually calls to another program:

Within fetch_image.cgi, read the image from the database, set the appropriate headers, and print the image:

use CGI;
use DBI;

my $q     = CGI->new();
my $name  = $q->param( 'image' );
my $dbh   = DBI->connect( 'some', 'connection', 'options' );

my $sth   = $dbh->prepare(<<END_SQL);
SELECT
    content_type, image
FROM
    images
WHERE
    image_name = ?
END_SQL

$sth->execute( $name );

my ($type, $image) = $sth->fetchrow_array();

print $q->header( $type ), $image;
[download]

Database connecting and error checking are left as an exercise for the reader.