class Main {
    public static void main ( String args[] ) throws Exception {
	LDB ldb = new LDB();
	try {
	    ldb.open("School");
	    ldb.begin_transaction();
	    LDBobject x = ldb.query("select name from Instructors where ssn=35");
	    System.out.println(x);
	    System.out.println(ldb.query("element(" + x.ref() + ")").getString());
	    LDBobject y = ldb.query("select e.name                            "
				    + "from e in Instructors,                 "
				    + "     c in e.teaches                    "
				    + "where e.dept.name='D2' order by e.name ");
	    for(int i=0; i<y.size(); i++)
		System.out.println(y.nth(i));
	    ldb.update("element(select * from Instructors where ssn=67).degrees",
		       "set('PhD','MSECE')");
	    System.out.println(ldb.query("element(select * from Instructors where ssn=67).degrees"));
	    ldb.commit_transaction();
	    ldb.close();
	} catch (ServerError m) {
	    System.out.print(m);
	    ldb.close();
	}
    }
}