Complete Chapter Review questions
Complete Chapter Review questions
1. What are three categories that describe the nature of information resources? Give an example of each. How do you characterize the relationships within each category of information?
Structured information A sales transaction with clearly defined fields for date, customer number, item number, and amount. The relationship is straightforward as a customer would be directly related to his customer record and their order record
Unstructured information Manila folder containing assorted items about a lawsuit, such as photos, handwritten notes, newspaper articles, or affidavits. Relationship is hard to establish as data is presented as being separate and independent.
Semi-structured information A web page with a title, subtitle, content, and a few images. Like the structured information, relationships here are straightforward except that there is lack of a standardized definition of data that is strictly followed.
2. What is metadata? What does metadata describe for structured information? For unstructured information? Give an example of each type of metadata.
Metadata are descriptive data that provide the necessary information about various data. Metadata, for structured information gives a description of the information of tables, relationships, and fields. On the other hand, for unstructured information, Metadata gives a description of the properties of documents and other resources. Metadata are mostly adopted in web pages as it can give information about where to locate more information about a subject, describes the tools use to create it and specify the language the page is documented in.
3. What are the characteristics of information that affect quality? What are examples of each?
The characteristics of high quality information are timeliness, completeness, Duplication, accuracy, and consistency. A database design depending on the operation and type of data, may need to have a higher level of accuracy especially in the development of new business ideas that
aid in the achievement of organizational goals. The other attribute is Completeness which is crucial as failure to enter the full data could show just a small part of a picture, and this includes information such as the house address in a customer’s order. Consistency is crucial in determining the quality of information, for example, in entering phone number, the data is expected to have a consistency of 10 digits. The other characteristic is Duplication, which is crucial as information should be distinctive and unique, and not duplicated. Duplication of information can give misleading results and this is seen by the fact that customers can appear more than once in the records of customers just because of a change in address. Finally, the other characteristic is Timeliness and this is an aspect that is more important in situation where real time and current information as required such as the stock market.
4. What were the early design approaches to managing information resources?
Before the advent of database systems, businesses were forced to place their records and organized documents in envelopes that were placed in rows of small pigeonholes that were lined up across a wall. Later with the invention of Siebels vertical manila folders were adopted made keeping of records much easier as they could be neatly arranged in cabinet drawers.
5. What are the major disadvantages of file processing systems? What are four specific problems associated with file processing systems?
File processing systems has the following disadvantages: security problems, Integrity problems, Data redundancy, Data Isolation, Inconsistency, and Problems in accessing data.
Lack of data Integration: Integrating data from different systems is usually a great challenge and this is because for example the payroll system might maintain information about name, address, and pay history, but gender and ethnicity are in personnel records. If a manager wanted to compare pay rates by ethnicity, new programs were written to match up the records. Inconsistent Data Definitions: One problem that is often experienced with file processing is differences in codes and the format of data. A case in point, phone numbers are known for the fact that they could take multiple formats as they could have country codes, the could have dashes, which makes it formatted as text fields. As such it could be treated as texts at one instance and in another instance, be taken as numbers.
Data Dependence: This is a problem that is mostly experienced during maintenance, as various programs had defined fields, formats, and business rules that are hard-coded and embedded
in the programs. As such, even a single step to try and accommodate a simple new business strategy becomes very hectic and involving.
6. Following the file processing model of data management, what three architectures emerged for integrated databases? What are the advantages of each? Are there disadvantages?
Hierarchical architecture
This is a model that arranges data in a “tree” structure, and it is presented almost in the scheme of files and folders in a computer. The data is presented in levels so that there are parent records and thus the relationships is presented in a format of parent/child relationship. One challenge is that it is hard to create link within data in the same level. Hierarchical system is crucial for systems such as library systems and phone contact records.
Network Architecture
A network Architecture resembles a lattice or web rather than the upside-down tree. Records can be linked in multiple ways, supporting many-to-many relationships. It allows multiple records to be linked to one file. It allows various databases and information to be interconnected but the number of links are large and thus it becomes complex, slow, and difficult to implement.
Relational architecture
The relational architecture solves the one to many relationships as data are presented in multiple tables that each have a unique identifier that can be the primary or foreign key used in linking data between tables. The architecture enables all the types of linkages and relationships. Relational databases prevent errors by allowing one record to apply to any number of other tables. By preventing duplication, the same information can be used in many different ways, without accidentally altering a record.
7. What are the steps in planning a relational data model? Are there benefits to the planning stage?
Steps of planning: Establishment of the required information, listing of the fields required and the able to contain the information and subsequent entry of the information, Planning and establishing the correlation between entities, and normalization process. Though planning can be time consuming it helps in coming up with a solid operational scheme that ensures that all the
functions that would require informational support is captured, which later saves on the time that would have been spent on saving changes later.
8. What are primary keys and foreign keys? How are they used to create links between tables in a relational database?
The primary key is defined as field, or a group of fields, that makes each record unique in a table, while the foreign keys are the primary keys that appear as an attribute in a different table are a foreign key in that table. They can be used to link the records in two tables together, as using foreign key reference a column holding the primary can be linked with another table holding the foreign key. The second column holding a primary key is defined as a foreign key.
9. What is the typical strategy to access a database? How do users access an Access database? Are there other strategies to access database systems?
Data is typically accessed through applications that can store, retrieve and manage data. Applications are crucial in providing easier tools of accessing a database while at the same time putting in place security features that ensure that access of databases is secured. In MS Access, databases are accessed through the use form generating and report writing. The are other strategies that are useful in accessing various databases and this includes the use of data command objects such as SQL statements.
10. What is the role of the database administrator in managing the database? What is the career outlook for this job?
From the job advert listed in the book, it is clear that there are two roles of a DBA: maintenance of production databases, which involves planning, designing, and development of new applications that will be used by an organization in accessing the Databases, and the management of an organizations data and information. Across the US, the role of a Database Administrator is very lucrative, and has become one of the fastest careers and is now competing with engineering and medicine as some of the most paying careers.
11. What is SQL? How is it used to query a database?
SQL is a language that is used to enable communication with databases and it is defined as the standard language that is adopted for relational database management systems. Database adopts the use of query so as to enable the functions of updating, deleting, or retrieving data from a database.
12. What is IVR? How is it used to query a database?
Interactive voice response (IVR) is a technology that facilitates access to the database from signals transmitted by telephone to retrieve information and enter data. The technology involves the preprogramming of various prompts that are prerecorded and can be easily recognized from a caller and depending on the command received, they access data in a database.
13. What is a shadow system? Why are shadow systems sometimes used in organizations? How are they managed? What are the advantages of shadow systems? What are the disadvantages?
Shadow system is a term that is used in reference to any system that operates outside the linkage of a centralized information system. It is a system that a creator designs separately so that it helps them solve a few issues they may experience in the workplace. Since it is not linked to the centralized system there could be inconsistencies as it could have different data to the contained by the organization’s information system. The systems are not complex and easy to sue, and as they involve simple modules then it can execute tasks quickly. It simplicity can be seen from the fact that it can be developed from Excel and Access. One problem with the system is that they are not secured, and documented and thus incase the creator leaves an organization, it becomes very hard to readopt the systems for future operations.
14. What is master data management? What is a data steward? What is the role of master data management in an organization’s integration strategy?
From the description, it is clear that master data management is an integration process that tries and create a uniform definition and attributes so that an organization can link all its data to one master file, so that the whole organization has a uniform point of reference. Data steward is a combination of watchdog and bridge builder, a person who ensures that people adhere to the definitions for the master data in their organizational units. Master data management can aid a company in the integration of all the modules in a business as they all access the same file and executes operations on one database so that it becomes easier to track all the operations of the different departments.
15. What is a data warehouse? What are the three steps in building a data warehouse?
The data warehouse is a central data repository containing information drawn from multiple sources that can be used for analysis, intelligence gathering, and strategic planning. The three key steps that are involved in the process of building data warehouse are Extract, Transform, and load. The first step is that of extraction of data, followed by transforming, and later cleansing which ensures that it adheres to the common data definitions.
16. What are examples of internal sources of data for a data warehouse? What are examples of external sources of data for a data warehouse?
Internal source of data includes operational data from the company, customer records, inventory, assets, demographic data, transactions, liabilities, human resource information, past shipments and website traffic.
External sources of data include competitor information, Census Data, and GPS coordinates.
17. What are four examples of data warehouse architectures? Which approach is suitable to meet today’s growing demand for real-time information?
Examples of data warehouse architectures: in memory database, Data Warehouse appliance, Relational Database, Virtual federated warehouse, and Data Cubes. Virtual federated warehouse adopts the use of extraction and transformation of data in real time and thus it is able to avail real time data required by various application, meeting demands for real time information.
18. What is big data? What are the defining features of big data?
Big Data is the collection of various information that vary in content, enormous in size, and accumulate at a rate that is so fast that it become difficult to store and analyze. The defining features of big data include velocity, variety, and Volume.
19. What is data mining? What is the difference between data mining and data dredging? What is the goal of data mining?
Data mining is an intelligent system of gathering information and incorporating the use of statistical tools so to be able to analyze large data, develop associated algorithms that define a relational pattern and hunt for hidden patterns. Data mining involves a systematic analysis of data that often yields important information while data dredging tries to sniff out relationships, which makes it hard to find a real pattern and with this method, relationships are often found by chance.
20. What are examples of databases without boundaries?
The other information management aspect is database without boundaries where people from outside an enterprise can enter and manage the records in a system. Instagram and Facebook are example of systems that have the aspect of database without boundaries as there are not limitation on the functionalities that an individual can perform. For example, one can delete their own Facebook account, apart from the other functionalities of uploading photos and performing other editing and modification functionalities. Currently, most of the ecommerce and job
advertising websites such as Craigslist have adopted an approach where customers are the one who manage records that are posted. In the ecommerce sectors, sellers can post the products that they have in some sites, and they can perform various functionalities on their records.
21. How do ownership issues affect information management? How do information management needs differ among stakeholder groups?
Information management is affected by ownership issues and this is because in an organization there are usually barriers and protective measures that are adopted so as to minimize on access to certain information. In an organization, departments may create level of access which limits the access to information while for a salesperson, they may want to keep their sales leads contacts private. There are different information needs for different stakeholder groups and this is seen from the fact that for example top-level information needs strategic information, whereas customers need simpler information with an easy interface.