AFAIK, the best practices say that you should never updated fact table rows, at least for transaction and periodic snapshot grains. While reading about Fact Table Surrogate Key, found a notion of updates:
Certain ETL techniques for updating fact rows are only feasible if a surrogate key is assigned to the fact rows. Specifically, one technique for loading updates to fact rows is to insert the rows to be updated as new rows, then to delete the original rows as a second step as a single transaction. The advantages of this technique from an ETL perspective are improved load performance, improved recovery capability and improved audit capabilities. The surrogate key for the fact table rows is required as multiple identical primary keys will often exist for the old and new versions of the updated fact rows between the time of the insert of the updated row and the delete of the old row.
Did Bob Becker mean updates/deletes from fact table? Is it a common practice?
