Error: DynamoDB Expression Not Null

What's Causing This Error

Update expressions and condition expressions are used by the update and delete operations of DynamoDB to determine which items are to be deleted or updated and how to update them. When the operation's expression attribute values are left undefined (null) when you are trying to update or delete an item, this error occurs as a result.

Solution: Here's How To Resolve It

To resolve this error, ensure that you provide not null values for every expression attribute value that is used in operation. You can either manually specify the values in the delete or update request or set the values before the operation execution by using the AWS SDK. You can also utilize if_exists or if_not_exists functions in the condition expression or the update expression to update or delete an item based on the attribute's existence.