Database Concepts (7th Edition)
7th Edition
ISBN: 9780133544626
Author: David M. Kroenke, David J. Auer
Publisher: PEARSON
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Textbook Question
Chapter 2, Problem 2.21RQ
Explain three possible interpretations of a null value.
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10. Sometimes logic for a query can be quite complex. It is possible to produce the desired
outcomes through the use of subqueries, inline views, and UNION-type statements. For those
methods, the transitional results are not saved in the database but are directly used within the
query. This can lead to achievement issues, particularly when the transitional results have a huge
number of
Explain.
a. columns
b. rows
c. reports
d. databases
Do we consider NULL values the same as that of blank space or zero in databases?
When writing queries in a programming language, why should we avoid creating a query by concatenating strings and instead use prepared statements or stored procedures in defense against SQL injection?
a.
concatenating strings helps prevent sql injection
b.
prepared statements or stored procedures help prevent the user/hacker from deliberately modifying the query by injecting sql instructions in the input values
c.
prepared statements prevent the query from taking as long to execute
d.
prepared statements enable the developer to just supply values without injecting sql
Chapter 2 Solutions
Database Concepts (7th Edition)
Ch. 2 - Prob. 2.1RQCh. 2 - Define the term entity, and give an example of an...Ch. 2 - Prob. 2.3RQCh. 2 - Prob. 2.4RQCh. 2 - Prob. 2.5RQCh. 2 - Prob. 2.6RQCh. 2 - Prob. 2.7RQCh. 2 - Prob. 2.8RQCh. 2 - Prob. 2.9RQCh. 2 - Define the term unique key and give an example.
Ch. 2 - Prob. 2.11RQCh. 2 - Prob. 2.12RQCh. 2 - Prob. 2.13RQCh. 2 - Describe four uses of a primary key.Ch. 2 - Prob. 2.15RQCh. 2 - Prob. 2.16RQCh. 2 - Prob. 2.17RQCh. 2 - Explain the term foreign key, and give an example.Ch. 2 - Prob. 2.19RQCh. 2 - Prob. 2.20RQCh. 2 - Explain three possible interpretations of a null...Ch. 2 - Give an example of a null value (other than one...Ch. 2 - Prob. 2.23RQCh. 2 - Prob. 2.24RQCh. 2 - Prob. 2.25RQCh. 2 - Prob. 2.26RQCh. 2 - Prob. 2.27RQCh. 2 - Define the term primary key in terms of functional...Ch. 2 - Prob. 2.31RQCh. 2 - Examine the data in the Veterinary Office...Ch. 2 - Prob. 2.33RQCh. 2 - Describe a modification problem that occurs when...Ch. 2 - Prob. 2.35RQCh. 2 - Prob. 2.36RQCh. 2 - Prob. 2.37RQCh. 2 - Apply the normalization process to the Veterinary...Ch. 2 - Prob. 2.39ECh. 2 - Prob. 2.40E
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