CS 6400 Exam 2 – Complete Practice Question Bank
600 Exam-Style Questions with Verified Answers & Detailed Rationales
Course: CS 6400 – Database Systems Concepts and Design (Georgia Tech / OMSCS)
Exam: Exam 2
Format: Multiple Choice (4 options each)
Questions: 600
Answer Key: Immediately following each question
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EXAM OVERVIEW
Component Details
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Primary Domains Relational Model Foundations, Relational Algebra, Relational Calculus,
EER Modeling, EER-to-Relational Mapping, Functional Dependencies & Normalization, SQL
Query Concepts, Transaction/Concurrency Basics
Official Exam 2 Focus Relational algebra and calculus, EER mapping (Ch. 5, 8, 9)
Question Style Conceptual, applied, and analytical multiple-choice
Recommended Text Elmasri & Navathe, Fundamentals of Database Systems, 7th Ed.
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TABLE OF CONTENTS
Section Domain Question Range
,---------
1 Relational Model Foundations & Keys Q1 – Q80
2 Relational Algebra Q81 – Q220
3 Relational Calculus Q221 – Q300
4 EER Modeling Q301 – Q380
5 EER-to-Relational Mapping Q381 – Q460
6 Functional Dependencies & Normalization Q461 – Q530
7 SQL Query Concepts Q531 – Q580
8 Transactions, ACID & Concurrency Basics Q581 – Q600
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SECTION 1: RELATIONAL MODEL FOUNDATIONS & KEYS (Q1–Q80)
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Q1. What is a domain in the relational model?
A) The set of all tuples in a relation
B) The set of atomic values that an attribute can take
C) The primary key of a relation
D) The set of all relations in a database
Answer: B
Rationale: A domain defines the permissible atomic values for an attribute. It is the pool of
values from which actual attribute values are drawn.
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Q2. In the relational model, a tuple represents:
A) A column
B) A row
C) A table
D) A domain
Answer: B
Rationale: A tuple is a single row in a relation, representing one entity instance or record.
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Q3. Which of the following is TRUE about the relational model?
A) Tuples are ordered by primary key
B) Attributes are ordered
C) Tuples are unordered
D) Duplicate tuples are always allowed
Answer: C
Rationale: The relational model treats relations as sets; tuple order is not part of the model.
Attributes are ordered in the schema, but tuples are not.
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Q4. A superkey is best defined as:
, A) A minimal set of attributes that uniquely identifies a tuple
B) Any set of attributes that uniquely identifies a tuple
C) A foreign key with no nulls
D) A set of attributes that can contain nulls
Answer: B
Rationale: A superkey is any attribute set whose values uniquely identify tuples. Minimality
is not required for a superkey; that property defines a candidate key.
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Q5. A candidate key is:
A) Any superkey
B) A minimal superkey
C) A foreign key
D) Always composite
Answer: B
Rationale: Candidate keys are superkeys with no redundant attributes. Minimality
distinguishes candidate keys from general superkeys.
---
Q6. How many candidate keys can a relation have?
A) Exactly one
B) At most one
C) One or more
600 Exam-Style Questions with Verified Answers & Detailed Rationales
Course: CS 6400 – Database Systems Concepts and Design (Georgia Tech / OMSCS)
Exam: Exam 2
Format: Multiple Choice (4 options each)
Questions: 600
Answer Key: Immediately following each question
---
EXAM OVERVIEW
Component Details
------
Primary Domains Relational Model Foundations, Relational Algebra, Relational Calculus,
EER Modeling, EER-to-Relational Mapping, Functional Dependencies & Normalization, SQL
Query Concepts, Transaction/Concurrency Basics
Official Exam 2 Focus Relational algebra and calculus, EER mapping (Ch. 5, 8, 9)
Question Style Conceptual, applied, and analytical multiple-choice
Recommended Text Elmasri & Navathe, Fundamentals of Database Systems, 7th Ed.
---
TABLE OF CONTENTS
Section Domain Question Range
,---------
1 Relational Model Foundations & Keys Q1 – Q80
2 Relational Algebra Q81 – Q220
3 Relational Calculus Q221 – Q300
4 EER Modeling Q301 – Q380
5 EER-to-Relational Mapping Q381 – Q460
6 Functional Dependencies & Normalization Q461 – Q530
7 SQL Query Concepts Q531 – Q580
8 Transactions, ACID & Concurrency Basics Q581 – Q600
---
SECTION 1: RELATIONAL MODEL FOUNDATIONS & KEYS (Q1–Q80)
---
Q1. What is a domain in the relational model?
A) The set of all tuples in a relation
B) The set of atomic values that an attribute can take
C) The primary key of a relation
D) The set of all relations in a database
Answer: B
Rationale: A domain defines the permissible atomic values for an attribute. It is the pool of
values from which actual attribute values are drawn.
,---
Q2. In the relational model, a tuple represents:
A) A column
B) A row
C) A table
D) A domain
Answer: B
Rationale: A tuple is a single row in a relation, representing one entity instance or record.
---
Q3. Which of the following is TRUE about the relational model?
A) Tuples are ordered by primary key
B) Attributes are ordered
C) Tuples are unordered
D) Duplicate tuples are always allowed
Answer: C
Rationale: The relational model treats relations as sets; tuple order is not part of the model.
Attributes are ordered in the schema, but tuples are not.
---
Q4. A superkey is best defined as:
, A) A minimal set of attributes that uniquely identifies a tuple
B) Any set of attributes that uniquely identifies a tuple
C) A foreign key with no nulls
D) A set of attributes that can contain nulls
Answer: B
Rationale: A superkey is any attribute set whose values uniquely identify tuples. Minimality
is not required for a superkey; that property defines a candidate key.
---
Q5. A candidate key is:
A) Any superkey
B) A minimal superkey
C) A foreign key
D) Always composite
Answer: B
Rationale: Candidate keys are superkeys with no redundant attributes. Minimality
distinguishes candidate keys from general superkeys.
---
Q6. How many candidate keys can a relation have?
A) Exactly one
B) At most one
C) One or more
