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Introduction to Information Systems
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Objective:

  1. Explain the importance of implementing data resource management processes and technologies in an organization.
  2. Outline the advantages of a database management approach to managing the data resources of a business.
  3. Explain how database management software helps business professionals and supports the operations and management of a business.
  4. Provide examples to illustrate each of the following concepts: major types of database, data warehouses and data mining, logical data elements, fundamental database structures, and database development.
A. Case Study - group discussion. 30 minutes.

 

B. Foundation Data Concepts
2.1 Data is one of the most valuable resources a firm possesses. It is organized into a hierarchy that builds from the smallest element to the largest : bit, byte, field, record, file, and database. (See the figure below:)

 

2.2. An entity is a generalized class of objects for which data is collected, stored, and maintained. An attribute is a characteristic of an entity. Specific values of attributes - called data items - can be found in the fields of the record describing an entity. A data key is a field within a record that is used to identify the record. A primary key uniquely identifies a record, while a secondary key is a field in a record that does not uniquely identify the record.

2.3. The traditional approach to data management has been from a file perspective. Separate files are created for each application. This approach can create problems over time: as more files are created for new applications, data that is common to individual files become redundant. Also, if data is changed in one file, those changes might not be made to other files, reducing data integrity.

2.4. To address problems of traditional file-based data management, the database approach was developed. Benefits of this approach include reduced data redundancy, improved data consistency and integrity, easier modification and updating, standardization of data access, and more efficient program development.

Q: Describe the hierarchy of data.

Q: What are the advantages of the database approach to data management, as opposed to the traditional file-based approach?

C. Database Management Systems

3.1.A DBMS is a group of programs used as an interface between a database and application programs. When an application program requests data from the database, it follow a logical access path. The actual retrieval of the data follows a physical access path. Records can be considered in the same way: a logical record is what the record contains; a physical record is where the record is stored on storage devices .Schemas users used to describe the entire database, its record types, and their relationships to the DBMS.

< figure 2.1 is an example of a database management approach in a bank information system.>

3.2 The four major uses of a DBMS package are database development, database interrogation, database maintenance, and application development.

<figure 2.2 The four major uses of a DBMS package>

3.2.1 Database Development:

Database management packages like Microsoft Access or Lotus Approach allow end users to easily develop the databases they need. However, large organizations with client/server or mainframe-base systems usually place control of enterprise wide database development in the hands of database administrators (DBA) and other database specialists. This improves the integrity and security of organizational database. Database developers use the data definition language (DDL) in database management system like Oracle 8 or IBM's DB2 to develop and specify the data contents, relationships, and structure of each database, and to modify these database specifications when necessary. Such information is cataloged and stored in a database of data definitions and specifications called a data dictionary, which is maintained by the DBA.

The Data Dictionary. Data dictionaries are another tool of database administration. A data dictionary is a computer-based catalog or directory containing metadata, that is, data about data. A data dictionary includes a software component to manage a database of data definitions, that is, metadata about the structure, data elements, and other characteristics of an organization's database. For example, it contains the names and descriptions of all types of data records and their interrelationships, as well as information outlining requirements for end users' access use of application programs, and database maintenance and security. see <figure 3-3> < use expression builder>

<figure 3.3>

 

3.2.2 Database Interrogation:

The database interrogation capability is a major benefit of a database management system. End user can use a DBMS by asking for information form a database using a query language or a report generator. They can receive an immediate response in the form of visual display or printed reports. No difficult programming is required. They query language feature lets you easily obtain immediate responses to ad hoc data requests: you merely key in a few short inquiries. The report generator feature allows you to quickly specify a report format for information you want presented as a report.

<figure 3.4>

SQL Queries. SQL, or Structured Query Language, is a Query language found in many database management packages. The basic form of an SQL query is:

SELECT ... FROM.. WHERE...

SQL is used in several popular database packages today and can be installed on PCs and mainframes.

Graphical and Natural Queries. Many end user (and IS professionals) have difficulty correctly phrasing SQL and other database language queries. So most end user data management packages offer GUI (graphical user interface) point-and -click methods, which are easier to use and are translated by the software into SQL commands. See figure 3.5 and figure 3.6.

<figure 3.5>

<figure 3.6>

3.2.3 Database Maintenance:

The database of an organization need to be updated continually to reflect new business transactions and other events. Other small changes must also be made to ensure accuracy of the data in the databases. The database maintenance process is accomplished by transaction processing programs and other end user application packages, with the support of the DBMS.

3.2.4 Application Development:

DBMS package play a major role in application development. End users, systems analysts, and other application developers can use the internal 4GL programming language and built-in software development tools provided by many DBMS packages to develop custom application programs. For example, you can use a DBMS to easily develop the data entry screens, forms, reports, or web pages of a business application. A DMBSs also makes the job of application programmers easier, since they do not have to develop detailed data-handling procedures using a conventional programming language every time they write a program. Instead, they can include data manipulation language (DML) statements in their programs that call on the DBMS to perform necessary data-handling activities.

Q:Define DBMS ,SQL., DDL, and DML

Q:What are the major uses of a DBMS?

D. Using Access as an Example:
Download northwind.zip
E. Database Structure. - Using Word Processor. (40 minutes)

In this exercise, you have to use word processor as a tool to help you summarize some key points of different database structures.The material is in your handout.

E. Current Database Development

1Organizations are building data warehouse, which are relational database management systems specifically designed to support management decision making.

2. Multidimensional database and on-line analytical processing (OLAP) programs are being used to store data and allow users to explore the data from a number of different perspectives.

3. Data mining, which is the automated discovery of patterns and relationships in a data warehouse, is emerging as a practical approach to generate a hypothesis about the patterns and anomalies in the data that can be used to predict future behavior.

4. An object-relational database management system (ORDBMS) provides a complete set of relational database capabilities, plus the ability for third parties to add new data types and operations to the database. These new data types can be audio, images, unstructured text, spatial data, or time series data that require new indexing, optimization, and retrieval features.

5.Business intelligence is the process of getting enough of the right information in a timely manner and usable form and analyzing it so that it can have a positive impact on business strategy, tactics, or operations. Competitive intelligence is one aspect of business intelligence limited to information about competitors and how that information affects strategy, tactics, and operations. Counter-intelligence describes the steps an organization takes to protect information sought by " hostile" intelligence gatherers. Knowledge management is the process of capturing a company's collective expertise wherever it resides - in computers, on paper, or in people's heads - and distributing it wherever it can help produce the biggest payoff. The goal of knowledge management is to get people to record knowledge (as opposed to data ) and then share it.

<figure 5.1 How data mining extracts business knowledge form a data warehouse.>

 

Web Exercises:

Use a Web search engine to find information on one of the following topics: data warehouse, data mining, or OLAP. Find a definition of the term ,an example of a company using the technology, and two companies that provide such software. Cut graphics and text material from the Web pages and paste them into a word processing document to create a two-page report on your selected topic.