Database Systems: Design, Implementation, and Management: Chapter 1 Review Questions

1. Define each of the following terms:
a. data
b. field
c. record
d. file
Data: raw facts
Field: an attribute, same data type
Record: related data that describes an entity
File: a collection of related records.
2. What is data redundancy, and which characteristics of the file system can lead to it?
Data redundancy occurs when the same data are stored in multiple places unnecessarily.

The use of spreadsheets and tables in different parts of the organization can cause it.

3. What is data independence, and why is it lacking in file systems?
Data independence exists when you can change the data storage characteristics without impeding the program’s ability to access the data.
4. What is a DBMS, and what are its functions?
DBMS = Database Management System

a collection of programs that manages the database structure and controls access to the data stored in the database. (think electronic filing cabinet)

functions of a DBMS:

data dictionary management
data storage management
data transformation and presentation
security management
multi user access control
backup and recovery management
data integrity management
database access languages and application programming interfaces.
database communication interfaces.

5. What is structural independence, and why is it important?
When it is possible to make changes in the file structure without affecting the application program’s ability to access the data.
6. Explain the differences among data, information, and a database.
Data are raw facts that have not been processed. Information is data that has been processed and given context. Databases help to facilitate the manipulation of data to create information by providing an organizational structure that makes relationships and connections between data explicit.
7. What is the role of a DBMS, and what are its advantages? What are its disadvantages?
serves as the intermediary between the user and the database.

advantages:

improved data sharing
improved data security
better data integration
minimized data inconsistency
improved data access
improved decision making
increased end-user productivity

disadvantages:

increased costs
management complexity
maintaining currency
vendor dependence
frequent upgrade/replacement cycles

8. List and describe the different types of databases.
– single user database: supports only one user at a time.

– desktop database: a single user database that runs on a personal computer

– multi-user database: supports multiple users at one time.

– work-group database: a multi-user database that supports a small number of users (50 or less)

– enterprise database: a multi-user database that supports a large number of users (50+)

– centralized database: supports data located at a single site.

– distributed database: supports data distributed across several different sites
– operational/transactional/production database: for day-to-day operations

– data warehouse: stores data used to generate info required to make tactical or strategic decisions

9. What are the main components of a database system?
hardware
software
people
procedures
data
10. What are metadata?
data about data, through which the end user data are integrated and managed.
11. Explain why database design is important.
a poorly designed database may produce difficult to trace errors that result in bad decision making — and bad decision making can lead to the failure of an organization.
12. What are the potential costs of implementing a database system?
– sophisticated hardware and software, trained personnel

– training, licensingm and regulation compliance costs

– vendor dependence – vendors are less likely to offer pricing point advantages to existing customers

– updating of hardware and software; additional training

13. Use examples to compare and contrast unstructured and structured data. Which type is more prevalent in a typical
business environment?
unstructured data is simply data that has not been processed to yield information.

examples of both types would include:

An invoice. If one were to take an invoice and simply scan it into a graphic, it would be unstructured data. In contrast, if it were processed and put into a database (subsequently becoming structured data), employees could eventually find the monthly averages, amount owed, etc. from various invoices.

While both are prevalent, I would think semi-structured data would be the most common in a typical business. Some data is stored but not processed (unstructured data such as memos), and some others are stored in databases (such as invoices) but most data are only processed to a certain extent that is displayed in a prearranged format but not able to yield all of the information contained within.

14. What are some basic database functions that a spreadsheet cannot perform?
spreadsheets do not support basic functionality such as:

support for self-documentation through metadata
enforcement of data types or domains to ensure consistency of data within a column, defined relationships among tables, or contraints to ensure consistency of data across related tables.

15. What common problems does a collection of spreadsheets created by end users share with the typical file system?
Common problems with using both a collection of spreadsheets created by end users and the typical file system include:

lengthy development times
difficulty of getting quick answers
complex system administration
lack of security and limited data sharing
extensive programming

16. Explain the significance of the loss of direct, hands-on access to business data that end users experienced with
the advent of computerized data repositories
The loss of direct, hands on access to business data to end-users was significant because it gave them the tools to convert their data into the information they needed and manipulating the company data that would allow them to create new information.

However, it seperated end-users from data. While this increased security, prevented redundancy and the such, it also created a delay in which the end-user could request information from the data and when it was delivered by the DP.

17. Explain why the cost of ownership may be lower with a cloud database than with a traditional, company database.
Because you are outsourcing your data to a entity with large database assets, thus lowering costs. Also you eliminate costs in hardware and software required to maintain your own database.