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DROP VS DELETE VS TRUNCATE


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
Removes all rows from a table. The operation cannot be rolled back and no triggers will be fired. As such, TRUCATE is faster and doesn't use as much undo space as a DELETE.

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.

Drop and Truncate are DDL commands, whereas DELETE is a DML command.










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