This (ugly) code seems to "work" for me:

my($employee_name,$employee_salary,$employee_ph,$employee_id) = 5..8;

%database;
@employee_details=($employee_name,  $employee_salary,$employee_ph,"\n"
+);
$database{$employee_id}=(\@employee_details);

use Data::Dumper; $Data::Dumper::Sortkeys=1; print Dumper(\%database);

__END__

$VAR1 = {
          '8' => [
                   5,
                   6,
                   7,
                   '
'
                 ]
        };
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Tip #1 from the Basic debugging checklist: warnings