Chapter 9

1. Chapter 9

2. Problem 7 • -Scalability- More scalable then two tier • -Technological flexibility – Easier to change DBMS engines • -Lower long term costs • -better match of system to business needs • -Improved customer service • -Competitive advantage • -reduced risk

3. Problem/Exorcise 2 • Redistributing time management for the jobs that occur because of the new efficiency. • Conditioning the employees to new forms of habit to conform to the new system. • The price of the architecture, it could be expencive.

4. Problem/Exorcise 5 • Big business that saw opportunity online where the fastest to transfer, eBay, amazon and Wal-Mart are three. • Slower businesses are those who probably do not have competition.

5. Problem/Exorcise 6 Advantages • -Middleware can help organize and view the data. • -helps design the database • -makes it easy to connect to the database • -The user won’t have to know SQL or any language to design and implement their database. Disadvantages • -The middleware can have a low level fault tolerance. • -The middleware can have restrictions on what the user can do with the data.

6. Chapter 10

7. Question 4 • It allows the company to organize customers and their information. It can also be the whole means of organizing products and sales.

8. Question 5 • The database, a firewall to protect the database, a processor, applications, and the user.

9. Question 6 • XML Is a very good way to transfer data around to different programs. Its easily understood and very effective.

10. Question 9 • People allowing there data and company to be used online. This can cause great security risks for the company and the data if not handled properly.

11. Problem/Exorcise 5 • Doc(“PVFC.xml”)/tutors/[all]/description

12. Chapter 11

13. Question 4 • No single system of record • Multiple systems are not synchronized • Organizations want to analyze the activities in a balanced way • Customer relationship management • Supplier relationship management.

14. Question 12 • No a star schema is not a relational data model because it cannot deal with online transaction processing.

15. Question 14 • Not physically separate from the database, just uses a different view. Because they are not separate they can be created quickly and have a much higher performance. They are organic and have data that might not be planned. They have a sort life and are restrictive.

16. Question 16 • Business keys change over time and we need to be able to know earlier keys. Surrogate key allows us to change unknown keys. Allows us to keep track of non-key attribute values over time. They are also shorter and simpler.

17. Question 17 • It is important to be able to tell when a transaction happened. Time is also important because you cant compare data or the data is useless if you cant tell how it happened over time.

18. Chapter 12

19. Question 4 • Uniqueness- each entity exists no more then once. • Accuracy-All data correctly represents what it is supposed to. • Consistency-the data in the data values agree with what's put into the database. • Completeness- every value should have a not have a non value. • Timeliness-meets expectations for when the data needs to be put into the database. • Currency- Information must be current. • Conformance- value must meet the format. • Referential integrity- the data referring to must be accurate and must meet the current database requirements.

20. Question 7 • External data sources – lack of control of data quality. • Redundant data – Uncontrolled redundancy • Data entry – Poor data capture controls. • Lack of organizational comment- do not recognize poor data as an issue.

21. Question 10 • A person assigned the responsibility of ensuring that organizational applications properly support the organizations data quality. Usually just an assigned task not a full time job.

22. Question 11 • Data governance is for much larger sets of data that usually involves a committee but they have the same idea of supporting data quality for a database or a series of databases.

23. Question 12 • Conduct a data quality audit • Improve data capture process • Establish a data stewardship program • Apply TQM principles and practices • Apply modern data management technology • Estimate return on investment • Start a high quality data model

24. Chapter 13

25. Question 8 • 4 job skills required for data administrators • Data policies, procedures, and standards • Planning- providing leadership and the ability to plan • Data conflict resolution • Managing the information repository • 4 job skills required for database administrators • Selecting DBMS and related software tools • Installing and upgrading DBMS • Tuning database performance • Improving database query processing performance

26. Question 11 • Accidental losses, including human error, software, and hardware-caused breaches- user authorization, uniform software installations, and maintenance schedules can help prevent this. • Theft and fraud- physical security (locked in office) firewalls. • Loss of privacy or confidentiality- blackmail, loss of reputation, passwords, state and federal laws help stop this. • Loss of data integrity – backup and recovery procedures • Loss of availability – sabotage data or network to make it so customers cant get to data.

27. Question 12 • A view allows the user to see information of a database without allowing them to access the database. They are not adequate security measures because unauthorized persons can gain access to data by experimenting.

28. Question 15 • The advantage is performance. With a query that reads can run at the same time as a query that is updating data. With pessimistic queries run in a strict sequential order on data , a read will not be allowed to run until after the update. This could have a significant negative impact on performance and experience.