DBMS SQL set2

Which of the following constraint is used to verify the values?

• default

• primary key

• check

• not null

The concept that is used to represent the unknown values______.

  

• Null

• Records

• Empty

• Blank

A foreign key must_____

• be unique

• match the field value of a primary key in a related table

• be defined in all tables in the database

• not have a repeated values

    The aggregate function is _____.

• DEL()

• ADD()

• MINIMUM()

• AVG()

The transaction operation used to undo the transactions is _______.

• rollback

• undo

• delete

• update

SQL allows _______ as attribute values

  

• not null

• unique key

• null

• primary key

Primary key constraint does not allow ____ values.

• integer

• Duplicate

• character

• unique

   The operation supported by alter table command is ______ .

    

• insert

• modify

• update

• delete

. SQL provides a ______ clause which can appear in conjunction with a group by  

    clause

  

• check

• from

• select

• having

   The aggregate function used to find the total marks of student relation is ________.

• avg

• sum

• count

• max