如果您不需要查询数据中的属性，您可以使用@voscausa 提到的属性之一:

If you don't need to query for the attributes in data you can use one of the properties as mentioned by @voscausa:

Json 属性

class MyModel(ndb.Model):
  city = ndb.StringProperty()
  date = ndb.DateProperty()
  data = ndb.JsonProperty()

my_model = MyModel(city="somewhere", 
                   date=datetime.date.today(),
                   data={'keyword1': 3,
                         'keyword2': 5,
                         'keyword3': 1,})

结构化属性:

class Data(ndb.Model):
  keyword = ndb.StringProperty()
  count = ndb.IntegerProperty()

class MyModel(ndb.Model):
  city = ndb.StringProperty()
  date = ndb.DateProperty()
  data = ndb.StructuredProperty(Data, repeated=True)

my_model = MyModel(city="somewhere", 
                   date=datetime.date.today(),
                   data=[Data(keyword="keyword1", count=3),
                         Data(keyword="keyword2", count=5),
                         Data(keyword="keyword3", count=1)])
my_model.put()

这里的问题是过滤结构化属性.关键字的属性被视为并行数组.进行查询，例如:

The problem here is filtering for structured properties. The properties of Keyword are viewed as parallel arrays. Doing a query such as:

q = MyModel.query(MyModel.data.keyword=='keyword1',
                  MyModel.data.count > 4)

会错误地包含 my_model.

https://developers.google.com/appengine/docs/python/ndb/queries#filtering_structured_properties

使用 expando 模型可以工作并允许您查询关键字:

Using an expando model would work and allow you to query for keywords:

class MyModel(ndb.Expando):
  city = ndb.StringProperty()
  date = ndb.DateProperty()

m = MyModel(city="Somewhere", date=datetime.date.today())
m.keyword1 = 3
m.keyword2 = 5
m.keyword3 = 1
m.put()

q = MyModel.query(ndb.GenericProperty('keyword1') > 2) 

https://developers.google.com/appengine/docs/python/ndb/entities#expando