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Oracle - SQL - Delete, Drop, or Truncate

DELETE	The DELETE command is used to remove rows from a table.
	A WHERE clause can be used to only remove some rows.
	If no WHERE condition is specified, all rows will be removed.
	After performing a DELETE operation you need to COMMIT or ROLLBACK the transaction to make the change permanent or to undo it.
	Note that this operation will cause all DELETE triggers on the table to fire.
DROP	The DROP command removes a table from the database.
	All the tables' rows, indexes and privileges will also be removed.
	No DML triggers will be fired.
	The operation cannot be rolled back.
TRUNCATE	TRUNCATE removes all rows from a table.
	The operation cannot be rolled back and no triggers will be fired.
	TRUCATE is faster and does not use as much undo space as a DELETE.

TRUNCATE

BEGIN TRAN
TRUNCATE TABLE tranTest
SELECT * FROM tranTest
ROLLBACK
SELECT * FROM tranTest

DELETE

BEGIN TRAN
DELETE FROM tranTest
SELECT * FROM tranTest
ROLLBACK
SELECT * FROM tranTest

Truncate reset identity of table. Delete does not reset identity of table.

It locks the entire table. It locks the table row.

Its DDL(Data Definition Language) Its DML(Data Manipulation Language)

We can't use WHERE clause with it. We can use WHERE to filter data to delete.

Trigger is not fired while truncate. Trigger is fired.

Syntax : Syntax : TRUNCATE TABLE table_name 1) DELETE FROM table_name

2) DELETE FROM table_name WHERE
example_column_id IN (1,2,3)