Module query (2.21.0)

Create / interact with Google Cloud Datastore queries.

Classes

And

And(filters)

Class representation of an AND Filter.

BaseCompositeFilter

BaseCompositeFilter(operation=Operator.OPERATOR_UNSPECIFIED, filters=None)

Base class for a Composite Filter. (either OR or AND).

BaseFilter

BaseFilter()

Base class for Filters

Iterator

Iterator(
    query,
    client,
    limit=None,
    offset=None,
    start_cursor=None,
    end_cursor=None,
    eventual=False,
    retry=None,
    timeout=None,
    read_time=None,
)

Represent the state of a given execution of a Query.

Parameters
Name Description
query Query

Query object holding permanent configuration (i.e. things that don't change on with each page in a results set).
client Client

The client used to make a request.
limit int

(Optional) Limit the number of results returned.
offset int

(Optional) Offset used to begin a query.
start_cursor bytes

(Optional) Cursor to begin paging through query results.
end_cursor bytes

(Optional) Cursor to end paging through query results.
eventual bool

(Optional) Defaults to strongly consistent (False). Setting True will use eventual consistency, but cannot be used inside a transaction or with read_time, otherwise 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.
read_time datetime

(Optional) Runs the query with read time consistency. Cannot be used with eventual consistency or inside a transaction, otherwise will raise ValueError. This feature is in private preview.

Or

Or(filters)

Class representation of an OR Filter.

PropertyFilter

PropertyFilter(property_name, operator, value)

Class representation of a Property Filter

Query

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

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.
explain_options ExplainOptions

(Optional) Options to enable query profiling for this query. When set, explain_metrics will be available on the iterator returned by query.fetch().
Exceptions
Type Description
ValueErro if project is not passed and no implicit default is set.