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In ndb, how to request elements where property A is not in list B?

In ndb, to request items where the property Ais in a list B, you can do something like:

Item.query(Item.A.IN(B))

How can you query for elements where property A is not in list B?

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2 answers

It's impossible. Note that your IN query is actually automatically split into several different EQUALS queries for each item in list B and the results of the union are returned.

You can request everything and then manually filter and ignore the results that are in list B.

GAE , , .

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!

'x!= y AND x!= z' ndb, "NOT IN": (1):

checkList = ['cookieAck', 'newkey', 'tempCelsius']
query = UserSetting.query(Setting.name!=checkList[0])
for check in checkList[1:]:
  query = query.filter(ndb.AND(UserSetting.name!=check))

settings = query.fetch()

, (2):

  query = UserSetting.query(ndb.AND(ndb.AND(UserSetting.name!='cookieAck', UserSetting.name != 'newkey'), UserSetting.name != 'tempCelsius'))

, (3):

query = UserSetting.query(UserSetting.name!='cookieAck', UserSetting.name != 'newkey', UserSetting.name != 'tempCelsius')

:

Query(kind='UserSetting', filters=OR(AND(FilterNode('name', '<', 'cookieAck'), FilterNode('name', '<', 'newkey'), FilterNode('name', '<', 'tempCelsius')), AND(FilterNode('name', '<', 'cookieAck'), FilterNode('name', '<', 'newkey'), FilterNode('name', '>', 'tempCelsius')), AND(FilterNode('name', '<', 'cookieAck'), FilterNode('name', '>', 'newkey'), FilterNode('name', '<', 'tempCelsius')), AND(FilterNode('name', '<', 'cookieAck'), FilterNode('name', '>', 'newkey'), FilterNode('name', '>', 'tempCelsius')), AND(FilterNode('name', '>', 'cookieAck'), FilterNode('name', '<', 'newkey'), FilterNode('name', '<', 'tempCelsius')), AND(FilterNode('name', '>', 'cookieAck'), FilterNode('name', '<', 'newkey'), FilterNode('name', '>', 'tempCelsius')), AND(FilterNode('name', '>', 'cookieAck'), FilterNode('name', '>', 'newkey'), FilterNode('name', '<', 'tempCelsius')), AND(FilterNode('name', '>', 'cookieAck'), FilterNode('name', '>', 'newkey'), FilterNode('name', '>', 'tempCelsius'))))
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