8014568b_cle_Database_with_Arun_Kaushik__Delete
[Point] 8. High Water Mark [Truncate] Truncate will reset the High Water mark which is very important for performance point of view as in case of full table scan and full index scan oracle will read all the block under high water mark this makes a lot of difference in terms of performance. [Delete] 
Delete will not reset the high water mark See Listing 7 for more details.
Dive in Oracle Database with Arun Kaushik
Delete