my $conn = MongoDB::Connection->new(
    host => 'hostname', 
    port => 27017, 
    username=>'xxxx',
    password=>'xxxx',
    db_name => 'xxxx'
);
my $database   = $conn->get_database( 'xxxx' );
my $collection = $database->get_collection( 'student' );
my $data       = $collection->find({"id"=>"stu_7";});
#i want to check exit or status code here !!!!!!!
#......
 while (my $doc = $data->next) {
       my @qual=@{$doc->{'qualifications'}};
       print @qual;
    }