Upgrade logging improvements
Upgrade needs to have better logging - for example during an upgrade, the spimportinventory stored procedure was failing on a merge with SQL error 8672:
The MERGE statement attempted to UPDATE or DELETE the same row more than once. This happens when a target row matches more than one source row.
Tracking this down was difficult because of the MERGE statement - if each row were being processed separately, the specific problem data could be called out when an error occurs.