Computer Science Engineering (CSE) Exam  >  Computer Science Engineering (CSE) Tests  >  Test: Relational Model - Computer Science Engineering (CSE) MCQ

Test: Relational Model - Computer Science Engineering (CSE) MCQ


Test Description

10 Questions MCQ Test - Test: Relational Model

Test: Relational Model for Computer Science Engineering (CSE) 2024 is part of Computer Science Engineering (CSE) preparation. The Test: Relational Model questions and answers have been prepared according to the Computer Science Engineering (CSE) exam syllabus.The Test: Relational Model MCQs are made for Computer Science Engineering (CSE) 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests for Test: Relational Model below.
Solutions of Test: Relational Model questions in English are available as part of our course for Computer Science Engineering (CSE) & Test: Relational Model solutions in Hindi for Computer Science Engineering (CSE) course. Download more important topics, notes, lectures and mock test series for Computer Science Engineering (CSE) Exam by signing up for free. Attempt Test: Relational Model | 10 questions in 30 minutes | Mock test for Computer Science Engineering (CSE) preparation | Free important questions MCQ to study for Computer Science Engineering (CSE) Exam | Download free PDF with solutions
Test: Relational Model - Question 1

Choose the option that correctly explains in words, the function of the following relational algebra expressionσyear≥2009 (book ⋈ borrow)

Detailed Solution for Test: Relational Model - Question 1

To understand the function of the given relational algebra expression, let's break it down:

σyear≥2009(book⋈borrow)

  1. Natural Join (⋈): The expression book⋈borrow represents a natural join between the "book" and "borrow" relations. A natural join combines tuples from both relations based on common attributes.

  2. Selection (σ): The selection operator σyear≥2009 filters the result of the natural join to include only those tuples where the "year" attribute is greater than or equal to 2009.

Given these points, the expression σyear≥2009(book⋈borrow) performs a natural join of the "book" and "borrow" relations first and then selects those tuples from the resulting set where the "year" attribute is greater than or equal to 2009.

The correct explanation is: Selects all the tuples from the natural join of book and borrow wherever the year is greater than or equal to 2009

Test: Relational Model - Question 2

What is the method of specifying a primary key in a schema description?

Detailed Solution for Test: Relational Model - Question 2

We can specify a primary key in schema description by underlining the respective attribute with a bold line.

1 Crore+ students have signed up on EduRev. Have you? Download the App
Test: Relational Model - Question 3

What does the “x” operator do in relational algebra?

Detailed Solution for Test: Relational Model - Question 3

The “x” operator outputs all pairs of rows from the two input relations (regardless of whether or not they have the same values on common attributes). This operation is called as the Cartesian product operation and is similar to the Cartesian product of sets.

Test: Relational Model - Question 4

What is a foreign key?

Detailed Solution for Test: Relational Model - Question 4

A foreign key is an attribute of a relation that is initially a primary key of another relation. A foreign key usage preserves referential integrity.

Test: Relational Model - Question 5

Choose the correct statement regarding superkeys

Detailed Solution for Test: Relational Model - Question 5

A superkey is an attribute or a set of multiple attributes that can uniquely identify a tuple. It is used to differentiate between tuples.

Test: Relational Model - Question 6

Statement 1: A tuple is a row in a relation
Statement 2: Existence of multiple foreign keys in a same relation is possible

Detailed Solution for Test: Relational Model - Question 6

A tuple is a row is a relation. There can exist multiple foreign keys in the same relation because there can exist multiple attributes in the relation that are primary keys in two or more other relations.

Test: Relational Model - Question 7

An attribute is a __________ in a relation.

Detailed Solution for Test: Relational Model - Question 7

An attribute is a column in a relation. A tuple is a row in a relation.

Test: Relational Model - Question 8

What action does ⋈ operator perform in relational algebra

Detailed Solution for Test: Relational Model - Question 8

⋈ Outputs specified attributes from all rows of the input relation. Remove duplicate tuples from the output. The operation is called the join operation.

Test: Relational Model - Question 9

What is an Instance of a Database?

Detailed Solution for Test: Relational Model - Question 9

The state of the database system at any given point of time is called as an Instance of the database.

Test: Relational Model - Question 10

State true or false: If a relation consists of a foreign key, then it is called a referenced relation of the foreign key dependency.

Detailed Solution for Test: Relational Model - Question 10

If a relation has a foreign key, then it is called a referencing relation of the foreign key dependency.

Information about Test: Relational Model Page
In this test you can find the Exam questions for Test: Relational Model solved & explained in the simplest way possible. Besides giving Questions and answers for Test: Relational Model, EduRev gives you an ample number of Online tests for practice

Top Courses for Computer Science Engineering (CSE)

Download as PDF

Top Courses for Computer Science Engineering (CSE)