You will never be able to find out the 'last record' inserted unless you have a column in the table with time-stamp for each row inserted. ROWIDs are reused and ROWNUMs simply give a serial number to all records returned by the query.

'Relational' databases do not store records in a particular order (neither do they return them in the order they were inserted.)

For complete and indepth discussion on this question, see

http://www.oracle.com/oramag/oracle/...o61asktom.html