• When manipulating objects comprising large bulks of data, transactions may become much longer than usual. New
concepts are therefore needed to accommodate long-duration transactions, and in addition the concepts for recovery and
consistency control and their relationship to the transaction concept have to be reconsidered.
• Protection mechanisms have to be based on the notion of object which is the natural unit of access control in this
framework.
• For databases containing large numbers of data, archiving may become a major issue. Again, objects (and their versions,
if any) form the natural unit for this activity.