The "Obsolete" indicator

The Obsolete indicator is used in data marts with Type 2 dimensions and State Oriented Fact tables only. These type of tables store history, so the attribute OBSOLETE__INDICATION will always be present in data mart tables that contain the From Date and To Date attributes.

The Obsolete indicator is used in data marts when retroactive changes are applied. When a row is added to a table for an object in which the From Date is earlier than the date of the existing row, the existing row will be earmarked as obsolete by setting the value for OBSOLETE__INDICATION to the current run number of the data mark task.

If no retroactive changes are used in the data marts, the value for the OBSOLETE__INDICATION will be 0.

Rows in a dimension that become obsolete will also enforce changes to the Fact table. The references of the Fact table to the obsolete rows is updated automatically so that the current, correct rows are referenced. This means that obsolete rows are isolated, in the sense that they can be deleted without subverting the referential integrity of the data mart.

The reason Compose does not delete these rows is for auditing purposes. For instance, consider a report that was generated in the past (using the data mart) and now contains incorrect information. Inspecting the obsolete rows may account for the discrepancy (i.e. incorrect data in the database as opposed to a deliberate attempt to manipulate the data).