REVOKE

REVOKE:

• It used to remove the access allowed GRANT.
• REVOKE privileges is assigned not only on TABLE OBJECT, But also on VIEWS,SYNONYMS,SEQUENCES Etc..

Syntax:

Revoke <privilege1 [,privilege2...]> on <object name> FROM <user1>[,user | role, PUBLIC...];

Ex:

SQL>revoke select on student from NLO1,NLO2;

SQL>revoke all on emp from netlojava;

Types of Privileges:

      i) System Privileges:

They allow a user to perform certain action within the Database.

ii) Object Privileges:

An object privilege allow a user to perform certain actions on database Objects.

Checking the object privileges Granted:

The schema object that stores the information about the privileges granted is 'USER_TAB_PRIVS_MADE'.

The columns of 'USER_TAB_PRIVS_MADE':

SQL>desc USER_TAB_PRIVS_MADE;

SQL>select GRANTEE,TABLE_NAME,GRANTOR,PRIVILEGE from USER_TAB_PRIVS_MADE

            where TABLE_NAME='EMP';

·        The GRANT command is use to assign Object Privileges to users or group of users.