Descriptive Attribute
Hubs and Links provide a distinct list of all business keys ever recognized by the data warehouse. They are not end-dated and don’t provide any information about the current status of the record (e.g. if the business key is still valid / assigned to a business object).
It is required to define how to store the deleted flag (for example as a descriptive field next to other descriptive fields in a standard satellite) and how to identify the deletes by identifying the sub-set of business keys from the target hub (or relationships from the link) that don’t exist anymore in the staging area source table.
Without this descriptive flag, which indicates the current status of the record, the data in the data warehouse should be considered as inconsistent because hubs and links don’t implement effectivity.
Detecting deletes is an important process to ensure the consistency of the data warehouse. This solution describes how to detect deletes without requiring a Last Seen Date. The state of the record is expressed using a descriptive field in the staging area.
