Quiz Discussion

Which of the following can be addressed by enforcing a referential integrity constraint?

• 1]

  All phone numbers must include the area code

• 2]

  Certain fields are required (such as the email address, or phone number) before the record is accepted

• 3]

  Information on the customer must be known before anything can be sold to that custome

• 4]

  When entering an order quantity, the user must input a number and not some text (i.e., 12 rather than ‘a dozen’)

Which of the following is not an integrity constraint?

• 1]

  Not null

• 2]

  Positive

• 3]

  Unique

• 4]

  Check ‘predicate’

Which of the following is the right syntax for the assertion?

• 1]

  Create assertion ‘assertion-name’ check ‘predicate’;

• 2]

  Create assertion check ‘predicate’ ‘assertion-name’;

• 3]

  Create assertions ‘predicates’;

• 4]

  All of the mentioned

CREATE TABLE Employee(Empid NUMERIC NOT NULL, Name VARCHAR(20) , dept_name VARCHAR(20), Salary NUMERIC UNIQUE(Empid,Name));
INSERT INTO Employee VALUES(1002, Ross, CSE, 10000)
INSERT INTO Employee VALUES(1006,Ted,Finance, );
INSERT INTO Employee VALUES(1002,Rita,Sales,20000);

What will be the result of the query?

• 1]

  All statements executed

• 2]

  Error in create a statement

• 3]

  Error in insert into Employee values(1006,Ted,Finance, );

• 4]

  Error in insert into Employee values(1008,Ross,Sales,20000);

In order to ensure that the value of the budget is non-negative which of the following should be used? 

CREATE TABLE Manager(ID NUMERIC,Name VARCHAR(20),budget NUMERIC,Details VARCHAR(30));

• 1]

  Check(budget>0)

• 2]

  Check(budget<0)

• 3]

  Alter(budget>0)

• 4]

  Alter(budget<0)

Which of the following is used to delete the entries in the referenced table when the tuple is deleted in the course table?

CREATE TABLE course
( ...
FOREIGN KEY (dept name) REFERENCES department
... );

• 1]

  Delete

• 2]

  Delete cascade

• 3]

  Set null

• 4]

  All of the mentioned

____________ is preferred method for enforcing data integrity.

• 1]

  Constraints

• 2]

  Stored Procedure

• 3]

  Triggers

• 4]

  Cursors

Domain constraints, functional dependency and referential integrity are special forms of  _______

• 1]

  Foreign key

• 2]

  Primary key

• 3]

  Assertion

• 4]

  Referential constraint

To include integrity constraint in an existing relation use :

• 1]

  Create table

• 2]

  Modify table

• 3]

  Alter table

• 4]

  Any of the above

A foreign key is the one in which the ________ of one relation is referenced in another relation.

• 1]

  Foreign key

• 2]

  Primary key

• 3]

  References

• 4]

  Check constraint