Quiz Discussion

DELETE FROM r;   /* r - relation  */

This command performs which of the following action?

• 1]

  Remove relation

• 2]

  Clear relation entries

• 3]

  Delete fields

• 4]

  Delete rows

To remove a relation from an SQL database, we use the ______ command.

• 1]

  Delete

• 2]

  Purge

• 3]

  Remove

• 4]

  Drop table

Which of the following is true regarding views?

• 1]

  The user who creates a view cannot be given update authorization on a view without having update authorization on the relations used to define the view

• 2]

  The user who creates a view cannot be given update authorization on a view without having update authorization on the relations used to define the view

• 3]

  If a user creates a view on which no authorization can be granted, the system will allow the view creation request

• 4]

  A user who creates a view receives all privileges on that view

Which of the following is used to provide delete authorization to instructor?

• 1]

  CREATE ROLE instructor ;
  GRANT DELETE TO instructor;

   

• 2]

  CREATE ROLE instructor;
  GRANT SELECT ON takes
  TO instructor;

   

• 3]

  CREATE ROLE instructor;
  GRANT DELETE ON takes
  TO instructor;

   

• 4]

  All of the mentioned

The basic datatype char (n) is a _______ length character string and varchar (n) is _______ length character.

• 1]

  Fixed, equal

• 2]

  Equal, variable

• 3]

  Fixed, variable

• 4]

  Variable, equal

In the authorization graph, if DBA provides authorization to u1 which in turn gives to u2 which of the following is correct?

• 1]

  If DBA revokes authorization from u1 then u2 authorization is also revoked

• 2]

  If u1 revokes authorization from u2 then u2 authorization is revoked

• 3]

  If DBA & u1 revokes authorization from u1 then u2 authorization is also revoked

• 4]

  If u2 revokes authorization then u1 authorization is revoked

Which of the following is used to avoid cascading of authorizations from the user?

• 1]

  Granted by the current role

• 2]

  Revoke select on the department from Amit, Satoshi restrict;

• 3]

  Revoke grant option for select on the department from Amit;

• 4]

  Revoke select on the department from Amit, Satoshi cascade;

An attribute A of datatype varchar(20) has the value “Avi”. The attribute B of datatype char(20) has value ”Reed”. Here attribute A has ____ spaces and attribute B has ____ spaces.

• 1]

  3, 20

• 2]

  20, 4

• 3]

  20, 20

• 4]

  3, 4

INSERT INTO instructor VALUES (10211, ’Smith’, ’Biology’, 66000);

What type of statement is this?

• 1]

  Query

• 2]

  DML

• 3]

  Relational

• 4]

  DDL

Which one of the following is used to define the structure of the relation, deleting relations and relating schemas?

• 1]

  DML(Data Manipulation Langauge)

• 2]

  DDL(Data Definition Langauge)

• 3]

  Query

• 4]

  Relational Schema