CISC3000 Quiz 02 - Chapter 02 Introduction to the Relational Model

Question 8 For each attribute of a relation, there is a set of permitted values, called the ________ of that attribute.

Domain

Question 5 Consider attributes ID, CITY and NAME. Which one of this can be considered as a super key?

ID Here the ID is the only attribute which can be taken as a key. Other attributes are not uniquely identified.

Question 3 A domain is atomic if elements of the domain are considered to be ____________ units.

Indivisbile

Question 19 The _________ joins are SQL server default

Inner

Question 18 The _______ operator takes the results of two queries and returns only rows that appear in both result sets.

Intersect

Question 2 A _________ integrity constraint requires that the values appearing in specified attributes of any tuple in the referencing relation also appear in specified attributes of at least one tuple in the referenced relation.

Referential

Question 1 A ________ in a table represents a *relationship* among a set of values.

Row

Question 20 The most commonly used operation in relational algebra for projecting a set of tuple from a relation is ___

Select

Question 4 A relational database consists of a collection of

Tables

Question 12 The number of attributes in relation is called as its

a. Degree (or Arity)

Question 10 The _____________ is essentially used to search for patterns in target string.

a. Like Predicate

Question 17 A _____ is a pictorial depiction of the schema of a database that shows the relations in the database, their attributes, and primary keys and foreign keys.

b. Schema diagram

Question 9 If we want to retain all duplicates, we must write ________ in place of union.

b. Union all

Question 11 The intersection operator is used to get the _____ tuples.

c. Common

Question 7 Consider: Student(ID, name, dept name, tot_cred). Which attribute form the primary key?

c. ID

Question 6 Consider: ​course(course_id,sec_id,semester). Here the course_id,sec_id and semester are _________ and course is a _________

d. Attributes, Relation

Question 13 The subset of a super key is a candidate key under what condition?

d. No proper subset is a super key The subset of a set cannot be the same set. Candidate key is a set from a super key which cannot be the whole of the super set.

Question 14 The tuples of the relations can be of ________ order.

Any The values only count. The order of the tuples does not matter.

Question 15 Using which language can a user request information from a database?

c. Query

Question 16 Which one of the following cannot be taken as a primary key?

c. Street Street is the only attribute which can occur more than once.