Oracle Delete and system resources

When deleting data with delete, the SQL statement first finds the qualifying record and deletes it through a full table scan or an index scan. In this process, however, a lot of CPU resources, I/O resources, and undo data will be consumed. If you delete a large amount of data, it will greatly affect the performance of the system.

Disadvantages:

1	Consumes a lot of system resources (CPU,I/O)
2	Unable to free space to delete data
3	Cannot lower the high water mark line

Oracle Delete and system resources