@Test
public void valuesShouldReturnAllExceptSystemFields() throws JSONException, IOException {

    Child child = new Child();
    child.put("test1", "value1");
    for (Database.ChildTableColumn column : Database.ChildTableColumn.systemFields()) {
        child.put(column.getColumnName(), "test");
    }
    assertThat(child.values(), equalJSONIgnoreOrder("{\"test1\":\"value1\"}"));
}