DBMS (Keys) - Quizz 1

Which one of the following is a set of one or more attributes taken collectively to unique identify a record?

• Candidate key

• Sub key

• Super key

• Foreign key

Consider attributes ID, CITY and NAME . Which one of this can be considered as a super key?

• NAME

• ID

• CITY

• CITY, ID

A ------------ is a property of the entire relation, rather than of the individual tuples in which each tuple is unique.

• Rows

• Keys

• Attribute

• Fields

Which one of the following attribute can be taken as a primary key?

• Name

• Street

• Id

• Department

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

Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record?

• Candidate key

• Sub key

• Super key

• Foreign key

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

• Id

• Register number

• Dept_id

• Street

A combination of two or more columns used to identify particular rows in a relation is a(n) _____ .

• record

• field

• composite key

• foreign key

An attribute (or combination of attributes) used strictly for data retrieval purposes is called a ___________

• super key

• candidate key

• secondary key

• primary key

Can we define more than one primary key in a table?

• Yes

• No