Updates¶

Module: aiodynamodb.updates Import: from aiodynamodb import UpdateAttr

UpdateAttr¶

A DynamoDB update attribute path. Inherits from boto3 AttributeBase so placeholder handling reuses the same builder machinery as condition expressions.

Instantiate with a field path string, then chain one action method:

UpdateAttr("name").set("Alice")
UpdateAttr("email").remove()
UpdateAttr("login_count").add(1)
UpdateAttr("roles").delete({"admin"})

Action methods¶

.set(value: Any) -> UpdateAttr¶

Set the attribute to a value.

UpdateAttr("name").set("Alice Smith")
UpdateAttr("address.city").set("New York")
UpdateAttr("basket.items[1].qty").set(9)

.remove() -> UpdateAttr¶

Remove the attribute entirely (equivalent to DynamoDB REMOVE).

UpdateAttr("email").remove()

.add(value: Any) -> UpdateAttr¶

Add a number to a numeric attribute, or add elements to a DynamoDB set.

UpdateAttr("login_count").add(1)
UpdateAttr("tags").add({"new-tag"})

.delete(value: Any) -> UpdateAttr¶

Remove elements from a DynamoDB set attribute.

UpdateAttr("roles").delete({"admin"})

Path syntax¶

Hashing¶

UpdateAttr instances are used in set[UpdateAttr], so they are hashable. The hash is based on (action_type, attribute_name, frozen_value).

Action¶

class Action(Enum):
    SET = "SET"
    REMOVE = "REMOVE"
    ADD = "ADD"
    DELETE = "DELETE"

The action type set on an UpdateAttr after calling one of its action methods.

UpdateExpressionBuilder¶

Internal class used by the client to compile a set[UpdateAttr] into a DynamoDB UpdateExpression string with ExpressionAttributeNames and ExpressionAttributeValues.

You do not need to use this directly — it is invoked internally by db.update() and TransactUpdate.