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Python 3.10 is now generally available.

google.appengine.datastore.datastore_query.PropertyOrder

An immutable class that represents a sort order for a single property.

Inherits From: Order, expected_type

prop the name of the prop by which to sort.
direction the direction in which to sort the given prop.

datastore_errors.BadArgumentError if the prop name or direction is invalid.

direction

prop

Methods

cmp

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Compares the given values taking into account any filters.

This function can be used as the cmp argument for list.sort() and sorted().

This function is slightly more efficient that Order.key when comparing two entities, however it is much less efficient when sorting a list of entities.

Args
lhs An entity_pb2.EntityProto
rhs An entity_pb2.EntityProto
filter_predicate A FilterPredicate used to prune values before comparing entities or None.

Returns
An integer <, = or > 0 representing the operator that goes in between lhs and rhs that to create a true statement.

cmp_for_filter

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key

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Constructs a "key" value for the given entity based on the current order.

This function can be used as the key argument for list.sort() and sorted().

Args
entity The entity_pb2.EntityProto to convert
filter_predicate A FilterPredicate used to prune values before comparing entities or None.

Returns
A key value that identifies the position of the entity when sorted by the current order.

key_for_filter

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reversed

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Constructs an order representing the reverse of the current order.

This function takes into account the effects of orders on properties not in the group_by clause of a query. For example, consider: SELECT A, First(B) ... GROUP BY A ORDER BY A, B Changing the order of B would effect which value is listed in the 'First(B)' column which would actually change the results instead of just reversing them.

Args
group_by If specified, only orders on properties in group_by will be reversed.

Returns
A new order representing the reverse direction.

__eq__

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Return self==value.

__ne__

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Return self!=value.

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