Chapter 1 - OER University - Anvari.Net · Web viewThe DBMS (database management system) uses...

Chapter 7 Managing Data Resources 7-1

Chapter 7Managing Data Resources

True-False Questions

1. The benefits of a DBMS are immediately tangible.

Answer: False Difficulty: Easy Reference: p. 234

2. Excellent hardware and software will result in inefficient information systems if file management is poor.

Answer: True Difficulty: Easy Reference: p. 234

3. A record describes an entity.


4. In traditional file processing, each functional area, by developing its own specialized applications, contributes to data redundancy and wastes resources.

Answer: True Difficulty: Medium Reference: p. 236

5. A traditional file processing system cannot deliver ad hoc reports in a timely fashion.


6. A DBMS eliminates most of the data definition statements found in traditional programs.

Answer: True Difficulty: Hard Reference: p. 238

7. A data manipulation language is usually used to replace conventional third- and fourth-generation programming languages to manipulate the data in the database.

Answer: False Difficulty: Hard Reference: p. 239

8. More advanced data dictionaries are active in that related programs can automatically use changes in the dictionary.


9. The most popular type of DBMS today for PCs is the network DBMS.


10. The strength of the relational model is that it can relate data in two files if the files share a common data element.


11. The project operation creates a subset consisting of columns in a table.


7-2 Managing Data Resources Chapter 7

12. The hierarchical model DBMS is a later version of the relational model DBMS.

Answer: False Difficulty: Medium Reference: p. 243

13. Hierarchical structures are limited in that each child may have only one parent.

Answer: True Difficulty: Hard Reference: p. 243

14. IBM’s IMS is a reliable hierarchical system still in use by many banks.


15. Conventional DBMS can easily handle graphics-based and multimedia applications.


16. The two design exercises primary to the design of a database are logical and physical.


17. The entity-relationship diagram documents the physical design of the database.


18. Most relational databases in use today have become fully normalized over the time during which they have been used.


19. Distributed systems increase the vulnerability of a central site.


20. Local databases can create security problems by widely distributing access to sensitive data.


21. The intent of the data administration function is to define information requirements for the entire company, with direct access to senior management.


22. The end-user is the primary advocate in the organization for database systems.


23. The fundamental principle of data administration is to define ownership of data by the area that produces them.


24. The purpose of enterprise analysis is to identify the key entities, attributes, and relationships that constitute the organization’s data.



25. A database serves the same community of users as traditional systems.


26. OLAP is another term for multidimensional data analysis.


27. With traditional systems, what is immediately available is current data only.


28. The primary advantage of a data warehouse is that anyone can access and update the data stored in the data warehouse.


29. A major advantage to data warehousing is that key operational data is available in a consistent, reliable, accessible format.


30. A data mart is a subset of a hierarchical system.


31. Too many data marts create complexity, costs, and management problems.


32. Datamining helps companies engage in target marketing.


33. Datamining poses challenges to the protection of individual privacy.


34. Hypermedia databases store chunks of multimedia information in the form of nodes connected by links the user specifies.


35. With the hypermedia database approach, the relationship between records is less structured than in a traditional DBMS.


36. The hypermedia database approach enables users to access topics on a Web site in whatever order they wish.


37. Legacy databases can be linked to the Web via middleware and other software products.



38. The software between the Web server and the DBMS must always be an application server.


39. It costs more to add a Web interface in front of a legacy system than it does to redesign and rebuild the system to improve user access.


40. An advantage to using the Web to access an organization’s internal databases is that the Web interface requires no changes to the internal database.


Multiple- Choice Questions

41. Implementing a database requires widespread organizational change in:

a. the role of information.b. the allocation of power at senior management levels.c. the ownership and sharing of information.d. patterns of organizational agreement.e. All of the above

Answer: e Difficulty: Medium Reference: p. 234

42. The costs of moving to a database environment are:

a. tangible, low, and back-loaded.b. intangible, back-loaded, and long-term.c. short-term, expensive, and intangible.d. tangible, up front, and large in the short term.e. up front, intangible, and expensive.

Answer: d Difficulty: Medium Reference: p. 234

43. The benefits of moving to a database environment are:

a. tangible, low, and back-loaded.b. back-loaded, expensive, and short term.c. intangible, back-loaded, and long term.d. short term, expensive, and intangible.e. up front, intangible, and inexpensive.

Answer: c Difficulty: Medium Reference: p. 234

44. An effective information system provides users with:

a. inexpensive information.b. timely, accurate, and relevant information.c. everything they need to make decisions.


d. many reports from different angles.e. an enterprise system.

Answer: b Difficulty: Medium Reference: p. 234

45. Many organizations have inefficient information systems because of:

a. poor file management.b. management interference in MIS.c. lack of cooperation between staff and line departments.d. outdated computers and bad information.e. poorly-paid personnel.

Answer: a Difficulty: Hard Reference: p. 234

46. The data hierarchy goes from bits and bytes to:

a. entities, attributes, fields, and records.b. fields, attributes, entities, and records.c. fields, records, files, and databases.d. records, entities, fields, and databases.e. attributes, entities, records, and tuples.


47. A characteristic or quality describing an entity is called a(n):

a. field.b. tuple.c. key field.d. attribute.e. record.


48. Duplicate data in multiple data files is:

a. data redundancy.b. data multiplication.c. always necessary in networked databases.d. typical of the relational model.e. a characteristic of a hierarchy.

Answer: a Difficulty: Easy Reference: p. 237

49. In a traditional file environment, any change in data requires:

a. a different entity description.b. a change in all programs that access the data.c. management approval.d. data redundancy.e. a different data dictionary.


50. The DBMS acts as an interface between application programs and:


a. the user.b. the reporting facility.c. the logical design of the database.d. the physical data files.e. None of the above


51. The logical description of the entire database showing all the data elements and relationships among them best describes:

a. data definition language.b. data dictionary.c. physical schema.d. conceptual schema.e. subschema.


52. The specific set of data from the database that is required by each user or application program best describes:

a. data definition language.b. data dictionary.c. physical schema.d. conceptual schema.e. subschema.


53. SQL is:

a. a first-generation language.b. the standard data manipulation language for relational DBMS.c. the query language used for networked databases.d. never used for reports.e. a natural language approach to gathering information from databases.


54. Many data dictionaries can:

a. be used with a third- or fourth-generation programming language.b. set up the forms required by applications programs.c. be substituted for the data manipulation language.d. produce lists and reports of data use, program locations, etc.e. All of the above

Answer: d Difficulty: Hard Reference: p. 239

55. A relational DBMS model:

a. combines the hierarchical model and the network model.b. treats data as if they were stored in two-dimensional tables.c. makes reports more difficult to program.


d. shares common data elements with application programs.e. All of the above


56. The three basic operations used to develop useful sets of data in a relational database are:

a. sort, select, and report.b. combine, relate, and sort.c. select, project, and join.d. project, combine, and report.e. join, relate, and sort.


57. The hierarchical DBMS:

a. presents data to users in a treelike structure. b. allows one parent for each child.c. organizes data elements into segments.d. allows many children to one parent.e. All of the above


58. Hierarchical DBMS can still be found in:

a. older, less flexible management environments that do not understand modern media.b. large legacy systems that require intensive high-volume transaction processing.c. small new companies that do not need relational DBMS.d. object-oriented environments.e. companies using low-level programming languages.


59. The conceptual design of a database is:

a. more important than the physical design.b. an abstract model of the database from the business perspective. c. easier for a programmer to understand than the logical design.d. the actual arrangement of data on direct access storage devices.e. an easy-to-change data model.

Answer: b Difficulty: Easy Reference: p. 244

60. A methodology for documenting databases illustrating the relationship between various entities in the database best describes:

a. data flow diagram.b. state transition diagram.c. entity-relationship diagram.d. entity sequence diagram.e. object model.

Answer: c Difficulty: Hard Reference: p. 245


61. Database designers document the conceptual data model with:

a. normalization diagrams.b. an entity-relationship diagram.c. a distributed-hierarchical diagram.d. an entity-attributes diagram.e. a database model.

Answer: b Difficulty: Hard Reference: p. 245

62. To use a relational database model effectively:

a. three-dimensional models must be created.b. there must be a minimum of four relationships.c. flat files must be eliminated.d. complex groupings of data must be streamlined.e. All of the above


63. If a database has been carefully considered, with a clear understanding of business information needs and uses:

a. relationships arrange themselves.b. the database model will most likely be in some normalized form.c. each part will have only one supplier.d. repeating groups will occur.e. all the attributes will be listed first.


64. A distributed database:

a. can pose security problems.b. does not need to be updated often.c. is updated continuously at the central location.d. is on one client/server network.e. is usually in a small geographic area, such as a university.

Answer: a Difficulty: Medium Reference: p. 247

65. Distributed systems:

a. often can run on smaller, less expensive computers.b. increase service and responsiveness to local users.c. depend on high-quality telecommunication lines.d. pose security problems by widely distributing access to sensitive data.e. All of the above


66. The organizational interests served by the DBMS are _________________ than those in the traditional file environment.

a. narrower


b. easier to controlc. easier to understandd. much broadere. less secure

Answer: d Difficulty: Easy Reference: p. 248

67. Enterprise analysis:

a. is needed to develop databases.b. must be undertaken before the firm does business on the Internet.c. is not pertinent to database design and development.d. sets out specific procedures and accountabilities.e. is usually a security issue.

Answer: a Difficulty: Hard Reference: p. 248

68. Relational systems with fourth-generation query languages:

a. are outdated today.b. permit employees who are not computer specialists to access large databases.c. require extensive employee training before they can be accessed.d. are not useful to Internet companies.e. are not yet available to most businesses.


69. Multidimensional analysis:

a. enables users to view the same data in different ways using multiple dimensions.b. uses current data only.c. plots data on a variable line.d. is not good for historical data.e. is best used in larger companies.

Answer: a Difficulty: Easy Reference: p. 248

70. Under traditional data systems:

a. the IS department maintains tight control of all data and its distribution.b. data are easier to locate, but harder to keep secure.c. data are fragmented in separate operational systems.d. data are harder to locate, but easier to keep secure.e. None of the above

Answer: c Difficulty: Hard Reference: p. 249

71. OLAP stands for:

a. object-oriented layered application programming.b. object-relational legacy attributes placement.c. objective layered attributes processing.d. online legacy application placement.e. online analytical processing.



72. Data warehousing uses data from:

a. daily reports only.b. diverse applications and locations.c. diverse applications, but one location.d. many locations, but one application.e. primarily government locations.


73. Datamining:

a. cannot predict likely future behavior.b. finds hidden patterns and relationships in large pools of data.c. is illegal.d. is not accurate for small companies.e. looks only at broad areas, not detail.


74. Individual privacy can be threatened by:

a. older legacy systems.b. datamining.c. multidimensional modeling.d. data administration.e. database administration.


75. CGI:

a. stands for Consumer Graphic Interface.b. is a specification for transferring information between a Web server and a program

designed to accept and return data.c. is a corporate approach to data warehousing.d. is a search engine written using PERL.e. is always Java-based.


76. The major enterprise system vendors have enhanced their software so that users:

a. do not need to deal with privacy issues.b. organize data along traditional product lines.c. can make use of large public databases.d. can integrate different platforms in their information interface.e. can access enterprise data through a Web interface.


77. The principal types of DBMS today are:

a. hierarchical and legacy.b. legacy and object-oriented.


c. relational and legacy.d. relational and object-oriented.e. hierarchical and relational.


78. The organization’s data model should reflect:

a. its key business processes and decision-making requirements.b. its concern with security.c. management understanding of data processing.d. its connection to legacy systems.e. social awareness.

Answer: a Difficulty: Medium Reference: p. 257


Fill In the Blanks79. A(n) field is a grouping of characters into a word, a group of words, or a complete number.

Difficulty: Easy Reference: p. 235

80. A(n) record is a group of related fields.


81. A(n) file is a group of records of the same type.


82. A(n) database is a group of related files.


83. A(n) entity is a person, place, thing, or event about which information must be kept.

Difficulty: Medium Reference: p. 235

84. A(n) attribute is a piece of information describing a particular entity.


85. A(n) key field is the field in a record that uniquely identifies instances of that record so that it can be retrieved, updated, or sorted.


86. Data redundancy is the presence of duplicate data in multiple data files.


87. The close relationship between data stored in files and the software programs that update and maintain those data is called program data dependence.

Difficulty: Hard Reference: p. 237

88. A(n) database, by rigorous definition, is a collection of data organized to service many applications at the same time by storing and managing data so that they appear to be in one location.


89. A(n) database management system (DBMS) is special software to create and maintain a database and enable individual business applications to extract the data they need without having to create separate files or data definitions in their computer programs.


90. The logical view presents data as they would be perceived by end users or business specialists.



91. The physical view shows how data are actually organized and structured on physical storage media.


92. A subschema is the specific set of data from the database that is required by each user or application program.


93. A(n) data element is a field.


94. A(n) data definition language is the component of a database management system that defines each data element as it appears in the database.


95. A(n) data manipulation language is the language associated with a database management system that end users and programmers use to manipulate data in the database.


96. The standard data manipulation language for relational database management systems is SQL (Structured Query Language).


97. A(n) data dictionary is an automated or manual tool for storing and organizing information about the data maintained in a database.


98. A(n) relational DBMS is a type of logical database model that treats data as if they were stored in two-dimensional tables. It can associate data stored in one table to data in another as long as the two tables share a common data element.


99. A(n) tuple is a row or record in a relational database.


100. The select operation creates a subset consisting of all records in the file that meet stated criteria.


101. The join operation combines relational tables to provide the user with more information than is available in the individual tables.



102. The project operation creates a subset consisting of columns in a table, permitting the user to create new tables that contain only the information required.


103. A(n) hierarchical DBMS is an older logical database model that organizes data in a treelike structure.


104. A(n) network DBMS is an older logical database model that is useful for depicting many-to-many relationships.


105. A(n) object-oriented DBMS is an approach to data management that stores both data and the procedures acting on the data as objects that can be automatically retrieved and shared.


106. A(n) object-relational DBMS is a database management system that combines the capabilities of a relational DBMS for storing traditional information and the capabilities of an object-oriented DBMS.


107. A(n) entity-relationship diagram is a methodology for documenting databases illustrating the relationship between various entities in the database.


108. Normalization is the process of creating small, stable, and adaptive data structures from complex groups of data when designing a relational database.


109. A(n) distributed database is a database that is stored in more than one physical location.


110. Data administration is a special organizational function for managing the organization’s data resources; it is concerned with information policy, data planning, maintenance of data dictionaries, and data quality standards.


111. A(n) information policy is the set of formal rules governing the maintenance, distribution, and use of information in an organization.


112. Database administration refers to the more technical and operational aspects of managing data, including physical database design and maintenance.



113. The capability for manipulating and analyzing large volumes of data from multiple perspectives is called on-line analytical processing (OLAP).


114. A(n) data warehouse is a database with reporting and query tools that stores current and historical data extracted from various operational systems and consolidated for management reporting and analysis.


115. A(n) data mart is a small data warehouse containing only a portion of the organization’s data for a specified function or population of users.


116. Datamining is the analysis of large pools of data to find patterns and rules that can be used to guide decision making and predict future behavior.


117. A(n) hypermedia database is an approach to data management that organizes data as a network of nodes linked in any pattern the user specifies; the nodes can contain text, graphics, sound, full-motion video, or executable programs.


118. A(n) database server is a computer in a client/server environment that is responsible for running a DBMS to process SQL statements and perform database management tasks.


Essay Questions119. Discuss the issue of organizational change, especially changes in power

arrangements, which can occur when an organization institutes an organization-wide DBMS.

Implementing a database requires widespread organizational change in the role of information (and information managers), the allocation of power at senior levels, the ownership and sharing of information, and patterns of organizational agreement. A DBMS challenges the existing power arrangements in an organization and for that reason often generates political resistance. In a traditional file environment, each department constructed files and programs to fulfill its specific needs. Now, with a database, files and programs must be built that take into account the full organization’s interest in data. Although the organization has spent the money on hardware and software for a database environment, it may not reap the benefits it should because it is unwilling to make the requisite organizational changes.

120. Discuss the hierarchical organization of data in a typical database.

A bit is a one (1) or a zero (0), the smallest unit of data a computer can handle. Eight bits compose a byte, which normally stands for one character or letter. Characters make up


fields, which are named groupings of characters. A group of related fields creates a record, each of which describes one entity. A group of related records composes a file. Groups of related files compose a database. Each record must contain one field, called the key, which uniquely identifies that particular entity in the file. Linking fields that occur in both files through the key field of one of the files to the same field data in the second file can relate entities file-to-file.

121. Identify four problems endemic to the traditional file environment.

If each branch of the organization designs, manages, and keeps its own information, the problems of data redundancy, program-data dependence, inflexibility, poor data security, and inability to share data among applications will become apparent, and worsen, with time.

122. How does the database approach to data management increase the efficiency and effectiveness of an organization?

The DBMS (database management system) uses special software to create and maintain a central database available to everyone in the organization. This enables individual business applications to extract the data they need without having to create separate files or data definitions. The data are more secure because they are held in one place, more consistent and accurate because the same data are not kept in many separate files (each of which must be updated accurately when the data changes), and more flexible because the DBMS supports ad hoc inquiries.

123. What is meant by the term “normalization”? Why are some effective DBMS systems not completely normalized?

To use a relational database model effectively, complex groupings of data must be streamlined to eliminate redundant data elements and awkward many-to-many relationships. The process of creating small, stable data structures from complex groups of data is called “normalization”. The objective is to set the data files up so that each item of data required by the DBMS need be entered only once, then pulled for multiple reports as required by the various applications. Many real-world databases are not fully normalized because this may not be the most sensible way to meet their business information requirements. In a case where each single part is always ordered from the same manufacturer, and each manufacturer is responsible only for the one part it provides, fully normalizing the database would require two separate files—one for the parts, another for the manufacturer – which in this case would not be efficient.

124. Define each of the following pairs of terms, distinguishing between the members of each pair. Logical view and physical view; data definition language and data manipulation language; data dictionary and data element.

The logical view of the database is the representation of data, as they would appear to an application programmer or end user. The physical view of the data is the representation of data, as they would actually be placed on the physical storage media.

The data definition language is that component of a database management system that defines each data element as it appears in the database. The data manipulation language is the language associated with a DBMS that end users and programmers use to query the data in the database. SQL is the standard for relational DBMS.

The data dictionary is an automated or manual file that stores the descriptions of data elements and their characteristics, such as usage, physical representation, ownership, authorization, and security. A data element represents the field itself, with its name, the names that reference this element in specific systems. The individuals, business functions,


programs, and reports that use this data element are also identified.

125. Describe the three basic operations of the relational database.

The three basic operations are select, join, and project. The select operation creates a subset consisting of all records in the file that meet stated criteria. The project operation creates a subset consisting of columns in a table, permitting the user to create new tables that contain only the information required. The join operation combines relational tables to provide the user with more information than is available in the individual tables.

126. List and describe the four critical elements in a database environment.

The textbook identifies data administration, data planning and modeling methodology, database technology and management, and users as the four critical elements. Data administration is the special organizational function for managing the organization’s data resources; it is concerned with information policy, data planning, maintenance of data dictionaries, and data quality standards. Data planning and modeling methodology is the use of enterprise analysis to identify and address the information requirements of the entire organization, as opposed to the requirements of individual applications. Enterprise analysis identifies the key entities, attributes, and relationships that constitute the organization’s data.Database technology and management refers to the decisions and processes involved in the purchase of hardware and software and the identification of those in management who are responsible for specific areas of data gathering, maintenance, and reporting. Users are the individuals who actually manipulate the data gathered, creating and distributing the necessary reports.

127. Define and describe OLAP and its potential uses.

Online analytical processing provides powerful tools for the manipulation and analysis of large volumes of data from multiple perspectives or dimensions. It provides analyses that traditional database models cannot represent, such as the ability to compare and manipulate product, pricing, cost, region, or time period, each in relationship to any one of the others. These data views can become very complex, with one set nested within another. Senior management can use such views in planning long-range changes in the organization.

128. Define and describe data warehouses, data marts, and datamining. What is the major concern connected with the use of these tools?

Data warehouses are huge databases that store current and historical data extracted from various operational systems and consolidated for management reporting and analysis. A data mart is a small data warehouse containing only a portion of the organization’s data for a specified function or population of users. Datamining is the manipulation and analysis of large pools of data to find patterns and rules that can be used to guide decision making and predict future behavior. The major concern connected with the use of these tools involves privacy concerns—should companies be allowed to collect such detailed information about individuals and their behavior?

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