Python – Filtering by entity key name in Google App Engine on Python

google-app-enginegoogle-cloud-datastorepython

On Google App Engine to query the data store with Python, one can use GQL or Entity.all() and then filter it. So for example these are equivalent

gql = "SELECT * FROM User WHERE age >= 18"
db.GqlQuery(gql)

and

query = User.all()
query.filter("age >=", 18)

Now, it's also possible to query things by key name. I know that in GQL you do it like this

gql = "SELECT * FROM User WHERE __key__ >= Key('User', 'abc')"
db.GqlQuery(gql)

But how would you now use filter to do the same?

query = User.all()
query.filter("__key__ >=", ?????)

Best Answer

from google.appengine.api.datastore import Key
query.filter("__key__ >=", Key.from_path('User', 'abc'))

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To override something (or pass extra args), do this:

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That way you could pass dict of error messages to the second param, and get to it later with e.errors.

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Best Answer

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