|DEFAULT Values for Table Columns : Enhancements in Oracle Database 12c Release 1 (12.1) - This article describes the changes to table column defaults in Oracle Database 12c.|
Conqueror said...After inserting a record into the table using sequence.nextval, if the insert is rolled back, will the sequence be reduced by one?
No. This is the same with identity columns in Oracle. Sequence behaviour is unchanged in this respect. Similarly, turning off the database will cause gaps as cached sequence numbers will be lost.