title: Retroactive indexing in Google Cloud Datastore
body: <p>There are many properties in my model that I currently don't need indexed but can imagine I might want indexed at some unknown point in the future.  If I explicitly set <code>indexed=False</code> for a property now but change my mind down the road, will Datastore rebuild the entire indices automatically at that point, including for previously written data? Are there any other repercussions for taking this approach?</p>