Lvl 2 Relational Algebra

Consider the table from SHAADI database and what should be the domain of attribute 'Marital Status'

• A-Z,a-z

• Single,Married, Divorced

• 0-9

• Not defined

• Single,Married

Answer explanation

Domain means the Set of Permitted value for the particular attribute

Here in 'Marital Status', we are only allowing the three kind of information to improve the Integrity of table.

so it means that we are using 'Domain Integrity Constraint' to avoid any incorrect data to be inserted in the our table.

How many super Keys can be possible in this table

• 1

• 2

• 3

• 4

• 5

What is TRUE about Keys?

• Relational databases rely heavily on keys

• Any row or record in the table can be uniquely identified with this field

• Relationships between tables can also be established using it

• All of the above

What is Composite key in DBMS

• a combination of multiple columns

• a combination of multiple rows

• a combination of multiple tables

• None of above

Which of the following statements is TRUE?

• Both the candidate keys and the primary key are equally strong

• Both the candidate keys and the primary key are equally weak

• Candidate key is weaker than the Primary Key

• Primary key is weaker than the Candidate key

An attribute in a relation is a foreign key if the _______ key from one relation is used as an attribute in that relation.

• Candidate

• Primary

• Super

• Sub

The ______ is the one in which the primary key of one relation is used as a normal attribute in another relation.

• Referential relation

• Referencing relation

• Referenced relation

• Referred relation

Which one of the following cannot be taken as a primary key?

• Id

• Register number

• Dept_id

• Street

In order to perform Union operation on two relations, both operand and relations must be

• Union compatible

• Set compatible

• Difference compatible

• User compatible

SELECT operator works _____ wise whereas PROJECT operator works _______ wise.

• Row, Column

• Column, Row

• Row, Row

• Column, Column