8014568b_cle_Database_with_Arun_Kaushik__Delete
[Point] 7. Space De allocation or Space Utilization [Truncate] Truncate: When a table is truncated it will free the space allocated except in case of reuse storage clause. This space can subsequently be used only by new data in the table or cluster resulting from insert or update operations .All extents are de allocated leaving only the extents specified when the table was originally created .Example So if the table was originally created with min extents 3, there will be 3 extents remaining when the tables is truncated. When you truncate a table, NEXT is automatically reset to the last extent deleted. [Delete] 
No extent reset with delete when deleting rows from a table, extents are not de allocated, So if there were 50 extents in the table before the deletion, there will still be 50 after the deletion. See Listing 5 & 6 for more details
Dive in Oracle Database with Arun Kaushik
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