Consider Figure 1-12, which depicts a hypothetical three-tiered database archite
ID: 3549884 • Letter: C
Question
Consider Figure 1-12, which depicts a hypothetical three-tiered database architecture. Identify potential duplications of data across all the databases listed on this figure. What problems might arise because of this duplication? Does this duplication violate the principles of the database approach? Why or why not?
Figure 1-12
Consider Figure 1-12, which depicts a hypothetical three-tiered database architecture. Identify potential duplications of data across all the databases listed on this figure. What problems might arise because of this duplication? Does this duplication violate the principles of the database approach? Why or why not?Explanation / Answer
Certain principles guide the database design process. The first principle is that duplicate information (also called redundant data) is bad, because it wastes space and increases the likelihood of errors and inconsistencies. The second principle is that the correctness and completeness of information is important. If your database contains incorrect information, any reports that pull information from the database will also contain incorrect information. As a result, any decisions you make that are based on those reports will then be misinformed.
A good database design is, therefore, one that:
The design process consists of the following steps:
This helps prepare you for the remaining steps.
Gather all of the types of information you might want to record in the database, such as product name and order number.
Divide your information items into major entities or subjects, such as Products or Orders. Each subject then becomes a table.
Decide what information you want to store in each table. Each item becomes a field, and is displayed as a column in the table. For example, an Employees table might include fields such as Last Name and Hire Date.
Choose each table
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.