[Backup and recovery] combines Incremental backup and image copies

A zero-level Incremental backup is equivalent to a complete backup, which contains all used data file blocks.
RMAN> backup incremental level 0 database;

Level 1 differential backup is the default Incremental backup. This backup only contains the data blocks that have been changed since the last level 1 Cumulative backup or differential backup.
RMAN> backup incremental level 1 differential database;

Level 1 Cumulative Incremental Backup only contains the data blocks changed since the last level 0 backup.
RMAN> backup incremental level 1 cumulative database;

Generate image copies using tags.
RMAN> backup as copy incremental level 0 database tag db_whole_copy;

Subsequently, perform Incremental backup regularly and apply the backup to the original backup. Syntax:
Run {
Allocate channel d1 type disk;
Backup incremental level 1
For recover of copy with tag db_whole_copy
Database tag db_copy_upd;
Recover copy of database with tag db_whole_copy;
Delete backupset tag db_copy_upd ;}