In order to effectively address your question, I would like to take a moment and explain the characteristics of a Entity <https://cloud.google.com/datastore/docs/concepts/entities>. Each entity within Datastore has a key that uniquely identifies it. The key (as you provided) consists of the following components:
1. Namespace of the entity 2. The kind <https://cloud.google.com/datastore/docs/concepts/entities#kinds_and_identifiers> of entity (categorized for queries) 3. An Identifier <https://cloud.google.com/datastore/docs/concepts/entities#kinds_and_identifiers> for the individual entity (can be a key name string or a integer numeric id.) I will be assuming that you are referring to the integer numeric id for your question. As far as having two of the same numeric ID's goes, indeed it is possible and this can be done by having your application assign their own numeric IDs manually to the entitles being created. However, as indicated in the documentation here <https://cloud.google.com/datastore/docs/concepts/entities#kinds_and_identifiers>, "there is nothing to prevent a Datastore mode database from assigning one of your manual numeric IDs to another entity". You will have to implement the *allocateids() <https://cloud.google.com/appengine/docs/standard/java/javadoc/com/google/appengine/api/datastore/DatastoreService#allocateIds-java.lang.String-long->*method within your application which will allow you to obtain a block of IDs in order to avoid the conflict mentioned above. Also, since you mentioned that "Datastore is the one automatically generating the ids", the documentation found here <https://cloud.google.com/datastore/docs/concepts/entities#kinds_and_identifiers> states that the "automatic ID generator will keep track of IDs that have been allocated" and that Datastore "will avoid reusing them for another entity". Therefore to sum it all up, Yes you can achieve the goal you want. However, it would be a good idea to implement the best practices for it as well such as: manually assigning Ids with implementing *allocateids() <https://cloud.google.com/appengine/docs/standard/java/javadoc/com/google/appengine/api/datastore/DatastoreService#allocateIds-java.lang.String-long->* . I hope this helps! -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/8cef0d63-0f78-44b0-838a-06edd79ed05f%40googlegroups.com.
