Query data using the Java binding and OQL

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We show in this section how to query objects as defined in the ODL schema using the Java language binding and OQL.

static void query_students(org.eyedb.Database db)
   throws org.eyedb.Exception {
    org.eyedb.OQL oql = new org.eyedb.OQL(db, "select Student");
    org.eyedb.ObjectArray obj_arr = new org.eyedb.ObjectArray();
    oql.execute(obj_arr);
    int count = obj_arr.getCount();
    for (int n = 0; n < count; n++) {
        Student s = (Student)obj_arr.getObject(n);
        if (s != null) {
            System.out.println(s.getFirstname() + " " + s.getLastname());
        }
    }
}

static void query_courses(org.eyedb.Database db,
                          String firstname, String lastname)
    throws org.eyedb.Exception
{
    org.eyedb.OQL oql = new org.eyedb.OQL
        (db, "select c from Course c where " +
         "c.teacher.lastname = \"" + lastname + "\" && " +
         "c.teacher.firstname = \"" + firstname + "\"");

    org.eyedb.ObjectArray obj_arr = new org.eyedb.ObjectArray();
    oql.execute(obj_arr);
    int count = obj_arr.getCount();
    for (int n = 0; n < count; n++) {
        Course c = (Course)obj_arr.getObject(n);
        if (c != null) {
            System.out.println(firstname + " " + lastname + ": " +
                               c.getTitle() + " " + c.getDescription());
        }
    }
}

View the whole Java file

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