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WGU D427 OBJECTIVE ASSESSMENT
FINAL EXAM AND PRACT ICE EXAM
COMPLETE 300 QUESTIO NS
COVERING DATA MODELI NG, SQL
QUERIES, DATABASE DE SIGN,
NORMALIZATION, AND R ELATIONAL
DATABASE MANAGEMENT SYSTEMS.
Question :What are the three parts of a database model?
Correct answer:1. Data structures that prescribe how data
is organized. 2. Operations that manipulate data structures. 3. Rules that govern valid data.
Question :What is the relational model and who
introduced it?
Correct answer:The relational model is a database model
based on a tabular data structure, introduced by E. F.Codd of IBM in 1970.
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Question :What was the initial impediment to the
commercial adoption of relational databases in the early 1980s?
Correct answer:Processing speed. Early relational
products were not as fast as more established non- relational products.
Question :The relational model was originally developed
for which types of applications?
Correct answer:Transactional applications like banking
and airline reservations.
Question :What is the basic data structure of the relational
model?
Correct answer:A table, which consists of columns
(attributes) and rows (tuples).
Question :How is the relational data structure based on set
theory?
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Correct answer:A set is an unordered collection of
elements, and a table is a set of rows, meaning rows have no inherent order.
Question :Match the following terms: Table Column Row Data type with their equivalents in Mathematics and File processing.Correct answer:- Databases: Table, Column, Row, Data
type - Mathematics: Relation, Attribute, Tuple, Domain -
File Processing: File, Field, Record, Data type
Question :Name three relational operations and their
functions.
Correct answer:1. Select - selects a subset of rows of a
table. 2. Project - eliminates one or more columns of a
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table. 3. Join - combines two tables by comparing related columns.
Question :What is the result of a relational operation?
Correct answer:A table.
Question :True or False: An SQL statement can implement only one relational operation.
Correct answer:False. Most SQL queries implement
several operations.
Question :Give examples of relational rules.
Correct answer:1. Unique primary key. 2. Unique column
names. 3. No duplicate rows.
Question :What is an example of a business rule, and how
is it different from a relational rule?Correct answer:Example: Delete cascade is a business rule requiring that when a row in one table is deleted, related rows in another table are also deleted. It is