app-engine-ndb

in my app i need to remove a few of my models properties. i checked out this link but the first issue is that the properties are on a polymodel and there is no way im going to switch to an expando for the time to remove the properties, im not even shure what could happen if i change a polymodel to an expando . so how do i remove properties from existing entities? i was thinking to set all StringProperty to None and then remove these from the model schema and redeploy. one of those properties is a BooleanProperty , i can't set this one to None right?! or an ndb.PickleProperty ... how should i

My goal is to create an e-commerce website where customers can see related products on any product page (similar to amazon.com). I have no idea how to get started with such a daunting task. From my research, my guess is to do the following: Create a Category kind: class Category(ndb.Model): name = ndb.StringProperty() Whenever a product is created, associate it with a Category via an ancestral relationship: parent_category = ndb.Key("Category", "Books") new_product = Product( title="Coding Horrors Book", parent=parent_category).put() Now, on each product page, I can create a query to return a

I currently have an application running on appengine and I am executing a few jobs using the deferred library, some of these tasks run daily, while some of them are executed once a month. Most of these tasks query Datastore to retrieve documents and then store the entities in an index (Search API). Some of these tables are replaced monthly and I have to run these tasks on all entities (4~5M). One exemple of such a task is: def addCompaniesToIndex(cursor=None, n_entities=0, mindate=None): #get index BATCH_SIZE = 200 cps, next_cursor, more = Company.query().\ fetch_page(BATCH_SIZE, start_cursor

I have run into an interesting limit with the App Engine datastore. I am creating a handler to help us analyze some usage data on one of our production servers. To perform the analysis I need to query and summarize 10,000+ entities pulled from the datastore. The calculation isn't hard, it is just a histogram of items that pass a specific filter of the usage samples. The problem I hit is that I can't get the data back from the datastore fast enough to do any processing before hitting the query deadline. I have tried everything I can think of to chunk the query into parallel RPC calls to improve

I am using the Python 2.7 runtime with NDB from the 1.6.2 SDK on Google App Engine. I get the following error: BadRequestError: app s~myapphr cannot access app dev~myapphr's data Originating from this code: device = model.Key(urlsafe=device_id).get() I am accessing my app from dev.myapp.appspot.com that is aliased to myapphr. device_id was created on the same dev.myapphr version. What is going on? the dev server has a default default_partition of 'dev' and on production, HRD apps get a partition of 's'. If you create a urlsafe key on the dev server and store it as a string it will not work on