google app engine - Read from datastore not consistent -

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i new google app engine, trying sample code , stuck :(

below code:

datastore = datastoreservicefactory.getdatastoreservice();

    transaction txn = datastore.begintransaction();      entity oset = new entity("set", "set1");     datastore.put(oset);      entity oitem1 = new entity("item", "item1", oset.getkey());     oitem1.setproperty("qty", "two");     datastore.put(oitem1);      entity oitem2 = new entity("item", "item2", oset.getkey());     oitem2.setproperty("qty", "five");     datastore.put(oitem2);      query query = new query("item").setancestor(oset.getkey());       list<entity> oitems = datastore.prepare(query).aslist(fetchoptions.builder.withlimit(50));      for(entity : oitems) {         system.out.println("item qty: " + i.getproperty("qty"));     }      txn.commit();

i trying create 2 "item" entities 1 property "qty". these 2 "item" entities descendants of entity "set". not able retrieve "item" entities back. wrong query?

you need put txn.commit(); after datastore.put(oitem2); ensure write operation completed, after running query (with or without separate transaction) fetch correct results

hope helps.


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