Mumbai University > Information Technology > Sem 5 > Advanced Database Management System

Marks: 5M

Year: Dec 2015

• It’s used to grant the privileges to the users. For e.g. GRANT create table, create session to amit, Raj with GRANT OPTION;

• It’s also possible to cancel the privileges by using Revoke.

  Revoke create table, create session from amit, Raj

• Grant and Revoke commandos are known as data control language commandos DCL granting of privileges. The grant statement is used to give authorization to any particular user.

  Syntax:-

  Grant <Privilege list>
  On     <Table Name> To <User>
  

• Grant select on Stud-Into 70,41,42,43…

• Grant delete, select on Stud-into 70, 41.]
• Update (amount) on account 70,42;
• Grant all stud-into
• If we want to grant a privilege & to allow the user to pass the privilege to author user we have to with grant option.
• Grant select on stud-into to all with grant option with this user you can grant select privilege to any other user.

Revoke:-

• Revoke <privilege list=""> on from <user>

  Revoke select on stud-into from 41;

  • The revocation of a privilege from a user may cause other user to lose that privilege this behaviour is called cascading of Revoke. In most database system cascading is default behaviour.
  • Revoke select on stud-into from 41 restrict, with this system returns an error if there are cascading revoke & revocation with stop.
  • Revoke grant option for select on stud-into from 4.
  • Due to this command only grant option will be revoke from user 4, that is no, he can no grant privilege to any other user.