FiltersDone

Question type

Essay

Multiple Choice

Short Answer

True False

Matching

Exam 5: The Relational Database Model: Introduction

Show Answer

Share

---

All types

Filters

Study FlashcardsPractice ExamLearn

Question 31

Multiple Choice

Review LaterAdd Note

Review Later

All of the following are true about storing a one-to-one binary relationship in a relational database, except _____.

A) an additional relation must be added to the database
B) two additional relations must be added to the database
C) the primary key of one of the relations in placed in the other relation as a foreign key
D) the two relations involved in the one-to-one relationship can be combined into one relation
E) a particular value of the primary key of one relation is associated with exactly one value of the primary key of the other relation (or possibly with none)

F) A) and E)
G) C) and D)

Correct Answer

verified

Show Answer

Question 32

True/False

Review LaterAdd Note

Review Later

In an equijoin, one of the two identical join columns in the result is eliminated.

A) True
B) False

Correct Answer

verified

Show Answer

Question 33

True/False

Review LaterAdd Note

In a relational Join operation, the join attributes must have the same domain of values.

Performance issues delayed the introduction of relational database management systems as viable commercial products.

No two rows of a relation are identical.

Which of the following relational algebra commands or combination of commands is capable of retrieving one or more rows of a relation?

All of the following events and factors in the early 1980s led to the introduction of relational database management, except ____.

A relation's primary key field can have non-unique values.

The relational data model was first described in a paper by Dr. E. F. Codd in ____.

An attribute or combination of attributes that is a foreign key in one relation of a database must be ____ another relation in the database.

A foreign key must have unique values in the relation in which it is a foreign key.

In a relational Join operation, the join attributes must have the same attribute names.

The combination of a relational Select and a relational Project operation can return a single data value.

Depending on the circumstances, it is possible that a foreign key is part of the primary key of the relation in which it is a foreign key.

Which of the following relational algebra commands or combination of commands is capable of retrieving a single cell value from a relation?

Storing a many-to-many relationship in a relational database requires the creation of an additional relation.

In relational database terminology, the terms row and relation are synonymous.