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    Class Query (2.1.6) 

      Query 
 ( 
 client 
 , 
 kind 
 = 
 None 
 , 
 project 
 = 
 None 
 , 
 namespace 
 = 
 None 
 , 
 ancestor 
 = 
 None 
 , 
 filters 
 = 
 (), 
 projection 
 = 
 (), 
 order 
 = 
 (), 
 distinct_on 
 = 
 (), 
 )

    A Query against the Cloud Datastore.

    This class serves as an abstraction for creating a query over data stored in the Cloud Datastore.

    Parameters

    Name Description
    client Client

    The client used to connect to Datastore.
    kind str

    The kind to query.
    project str

    (Optional) The project associated with the query. If not passed, uses the client's value.
    namespace str

    (Optional) The namespace to which to restrict results. If not passed, uses the client's value.
    ancestor Key

    (Optional) key of the ancestor to which this query's results are restricted.
    filters tuple[str, str, str]

    Property filters applied by this query. The sequence is (property_name, operator, value) .
    projection sequence of string

    fields returned as part of query results.
    order sequence of string

    field names used to order query results. Prepend - to a field name to sort it in descending order.
    distinct_on sequence of string

    field names used to group query results.

    Inheritance

    builtins.object > Query

    Properties

    ancestor

    The ancestor key for the query.

    Returns
    Type Description
    Key or None The ancestor for the query.

    distinct_on

    Names of fields used to group query results.

    Returns
    Type Description
    sequence of string The "distinct on" fields set on the query.

    filters

    Filters set on the query.

    Returns
    Type Description
    tuple[str, str, str] The filters set on the query. The sequence is ``(property_name, operator, value)``.

    kind

    Get the Kind of the Query.

    Returns
    Type Description
    str The kind for the query.

    namespace

    This query's namespace

    Returns
    Type Description
    str or None the namespace assigned to this query

    order

    Names of fields used to sort query results.

    Returns
    Type Description
    sequence of string The order(s) set on the query.

    project

    Get the project for this Query.

    Returns
    Type Description
    str The project for the query.

    projection

    Fields names returned by the query.

    Returns
    Type Description
    sequence of string Names of fields in query results.

    Methods

    add_filter

      add_filter 
 ( 
 property_name 
 , 
 operator 
 , 
 value 
 )

    Filter the query based on a property name, operator and a value.

    Expressions take the form of::

    .add_filter('

    where property is a property stored on the entity in the datastore and operator is one of OPERATORS (ie, = , < , <= , > , >= )::

    from google.cloud import datastore client = datastore.Client() query = client.query(kind='Person') query = query.add_filter('name', '=', 'James') query = query.add_filter('age', '>', 50)

    Parameters
    Name Description
    property_name str

    A property name.
    operator str

    One of = , < , <= , > , >= .
    value `int`, `str`, `bool`, `float`, `NoneType`, `datetime.datetime`, Key

    The value to filter on.
    Exceptions
    Type Description
    `ValueError if ``operation`` is not one of the specified values, or if a filter names ``'__key__'`` but passes an invalid value (a key is required).
    Returns
    Type Description
    Query A query object.

    fetch

      fetch 
 ( 
 limit 
 = 
 None 
 , 
 offset 
 = 
 0 
 , 
 start_cursor 
 = 
 None 
 , 
 end_cursor 
 = 
 None 
 , 
 client 
 = 
 None 
 , 
 eventual 
 = 
 False 
 , 
 retry 
 = 
 None 
 , 
 timeout 
 = 
 None 
 , 
 )

    Execute the Query; return an iterator for the matching entities.

    For example::

    from google.cloud import datastore client = datastore.Client() query = client.query(kind='Person') result = query.add_filter('name', '=', 'Sally').fetch() list(result) [

    Parameters
    Name Description
    limit int

    (Optional) limit passed through to the iterator.
    offset int

    (Optional) offset passed through to the iterator.
    start_cursor bytes

    (Optional) cursor passed through to the iterator.
    end_cursor bytes

    (Optional) cursor passed through to the iterator.
    client Client

    (Optional) client used to connect to datastore. If not supplied, uses the query's value.
    eventual bool

    (Optional) Defaults to strongly consistent (False). Setting True will use eventual consistency, but cannot be used inside a transaction or will raise ValueError.
    retry `google.api_core.retry.Retry`

    A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
    timeout float

    Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
    Returns
    Type Description
    `Iterator` The iterator for the query.

    key_filter

      key_filter 
 ( 
 key 
 , 
 operator 
 = 
 "=" 
 )

    Filter on a key.

    Parameters
    Name Description
    key Key

    The key to filter on.
    operator str

    (Optional) One of = , < , <= , > , >= . Defaults to = .

    keys_only

      keys_only 
 ()

    Set the projection to include only keys.
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