I try to use objectify transaction, but I have some issues when I need to reload an object created in the same transaction.
Take this sample code
@Entity
public class MyObject
{
@Parent
Key<ParentClass> parent;
@Index
String foo;
}
ofy().transact(new VoidWork()
{
@Override
public void vrun()
{
ParentClass parent = load();// load the parent
String fooValue = "bar";
Key<ParentClass> parentKey = Key.create(ParentClass.class, parent.getId())
MyObject myObject = new MyObject(parentKey);
myObject.setFoo(fooValue);
ofy().save().entity(myObject).now();
MyObject reloaded = ofy().load().type(MyObject.class).ancestor(parentKey).filter("foo", fooValue).first().now();
if(reloaded == null)
{
throw new RuntimeException("error");
}
}
});
My object reloaded is always null, maybe I miss something, but logically within a transaction I can query an object which was created in the same transaction?
Thanks
Cloud Datastore differs from relational databases in this particular case. The documentation states that -
Unlike with most databases, queries and gets inside a Cloud Datastore transaction do not see the results of previous writes inside that transaction. Specifically, if an entity is modified or deleted within a transaction, a query or lookup returns the original version of the entity as of the beginning of the transaction, or nothing if the entity did not exist then.
https://cloud.google.com/datastore/docs/concepts/transactions#isolation_and_consistency
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