Difference between TRUNCATE, DELETE and DROP commands

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.

Drop :- Drop command remove a table from the database.All the table's rows,indexes,privileges will also be removed.No DML
triggers will be fired. The operation can not be rollback.


Drop and Truncate  are DDL commands,whereas DELETE  is a DML command.Therefore delete operations can be roll



TRUNCATE:

This is the DML command. This command delete the data from table. But there is one difference from delete command.
Truncate command drop the storage  structure & data  held by this table.
Drop storage can be use by this table again or some other table.
This is the faster command because it directly drop the storage