query.addFilter("Gender", Query.FilterOperator.EQUAL, gender.toString());
}
ArrayList<Key> dataEntryKeys = new ArrayList<Key>();
PreparedQuery pq = datastore.prepare(query);
for (Entity result : pq.asIterable()) {
Key patients_key = result.getKey();
Query data_query = new Query("DataEntry", patients_key);
PreparedQuery dq = datastore.prepare(data_query);
for (Entity de : dq.asIterable()) {
dataEntryKeys.add(de.getKey());