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6. Datastore Queries > Query Results and Keys

Query Results and Keys

When retrieving results for an entity query, the datastore returns the full entity for each result to the application.

For large entities, this may mean more data is transmitted between the datastore and the app than is needed. It’s possible to fetch only a subset of properties under certain circumstances (we’ll see this in Projection Queries), but these are not full entities. Another option is to store frequently accessed properties on one entity, and less popular properties on a separate related entity. The first entity stores the key of the second entity as a property, so when the app needs the less popular data, it queries for the first entity, then follows the reference to the second entity.


  

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