What is the difference between DROP, TRUNCATE, and DELETE? Explain and give exam

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DELETE: when u r using delete command in oracle the data will be deleted in the table. after that if u r using rollback the data in the table will be retrived.TRUNCATE: in the case of truncate, when u r using truncate what ever data in the table it will be deleted. after that if u r giving rollback also the data will not be retrived. but the structure of the table is available.DROP: in the case of DROP, if u r using drop the rollback command is not working and structure and data in the table also deleted. nothing willbe available about that table.EXAMPLE:DELETE: delete * from emp; "then the data inthe table will be deleted"after this u give ROLLBACKthen the data willbe retrieved. TRUNCATE: truncate table emp; " then the data inthe table willbe deleted" but the sturucture is available> if u type--- desc empthen it give the structure of that table.DROP: drop table emp:after that what ever command u r using on emp table it will give error. bcuz the table object emp is not available in database (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. TRUNCATE removes all rows from a table. The operation cannot be rolled back. As such, TRUCATE is faster and doesn't use as much undo space as a DELETE. The DROP command removes a table from the database. All the tables' rows, indexes and privileges will also be removed. The operation cannot be rolled back. DROP and TRUNCATE are DDL commands, whereas DELETE is a DML command. Therefore DELETE operations can be rolled back (undone), while DROP and TRUNCATE operations cannot be rolled back. From Oracle 10g a table can be "undropped". Example: SQL> FLASHBACK TABLE emp TO BEFORE DROP; Flashback complete.)

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