my $mysortref = sort_maker(
    sub { lc($data{$a}[0]) cmp lc($data{$b}[0]) },
    sub { lc($data{$a}[1]) cmp lc($data{$b}[1]) },
);

@results = sort $mysortref (keys %data);
print "@{$data{$_}}\n" for (@results);

sub sort_maker {
    my @littlesubs = @_;
    sub {
        foreach my $sub (@littlesubs) {
            my $result = $sub->();
            return $result if $result;
        }
    };
}

##</code><code>##

HERNANDEZ      HECTOR     456791 SAMSON 0217      2001-07-25 1963-08-01
VASQUEZ        JOAQUIN    456789 SAMSON 0209      1990-11-14 1970-03-25
JONES          TIMOTHY    803092 LAVER  0103      2001-03-19 1969-06-29
SMITH          BETTY_SUE  698389 SAMSON 0211      1992-01-23 1949-08-12

##</code><code>##

    lastname
    firstname
    cno
    unit
    ward
    dateadmission
    datebirth


##</code><code>##

  my %parameters = (
    lastname       => [ qw( U a ) ],
    firstname      => [ qw( U a ) ],
    cno            => [ qw( U n ) ],
    unit           => [ qw( U s ) ],
    ward           => [ qw( U n ) ],
    dateadmission  => [ qw( D a ) ],
    datebirth      => [ qw( D a ) ],
  );

##</code><code>##

    my $results_ref = 
        $dp->sort_by_column( qw{ lastname firstname cno } );

##</code><code>##

    sub { lc($data{$a}[0]) cmp lc($data{$b}[0]) },