CHAPTER SEVEN:STORING ORGANIZATIONAL INFORMATION DATABASES

LEARNING OUTCOMES

1.DEFINE THE FUNDAMENTAL CONCEPTS OF THE RELATIONAL DATABASE MODEL?

     Information is stored in databases.Databases maintains information about various types of objects(inventory),events(transactions),people(employees),and places(warehouses).Information is everywhere of organization.Database models include:

–Hierarchical database model – information is organized into a tree-like structure that allows repeating information (using parent/child relationships) in such a way that it cannot have too many relationships.Hierarchical structures were widely used in the first mainframe database management systems.Hierarchical structure often cannot be used to relate to structures that exist in the real words.

–Network database model – a flexible way of representing objects and their relationships.The network model allows each record to have multiple parent and child records,forming a lattice structure.

–Relational database model – stores information in the form of logically related two-dimensional tables.

          One way to think about data in a relational database is to think about a cube of data. For example, at The Gap, the CEO, the district managers and the sales managers might think about their business as selling products (jeans, sweaters) in many markets (stores, regions) and measuring their progress over time (days, weeks, months). Many of the questions these managers have about their business can be answered by looking to the intersection of data defined by the edges of the cube pictured in Figure 1.

 

FIGURE 1

2)EVALUATE THE ADVANTAGES OF THE RELATIONAL DATABASE MODEL?

From a business perspective,databases information offers many advantages,including:

INCREASED FLEXIBILITY

           -Good databases can handle a changes quickly and easily,just as any good business     needs to be able to handle changes quickly and easily.Databases provide flexibility in allowing each user to access the information in whatever way best suits his or her needs.The distinction between logical and physical views is important in understanding flexible databases user views.

–Have only one physical view

Physical view – deals with the physical storage of information on a storage device such as a hard disk

–Have multiple logical views

             Logical view – focuses on how users logically access information to meet their particular business needs.

           This separation of logical and physical views is what allows each user to access database information differently.Database has only one physical views it can easily support multiple logical views.Foe example is a mail-order business.One user might want a CRM report presented in alphabetical format,in which case last name should appear before first name.Another user,working with catalog mailing system,would want customer names appearing as first name and then last name.Both are easily achievable but different logical views of the same physical information.

INCREASED SCALABILITY AND PERFORMANCE

-           A database must scale to meet increased demand,  while maintaining acceptable performance levels.Only a databases could "scale"to handle the massive volumes of information and the large numbers of users required for the successful launch of the Ellis Island website.

–Scalability – refers to how well a system can adapt to increased demands

–Performance – measures how quickly a system performs a certain process or transaction

          Some organization must be able to support hundreds or thousands of online users including employees,partners,customers and suppliers who all want to access and share information.

REDUCED INFORMATION REDUNDANCY

        -   Redundancy is the duplication of information or storing the same information in multiples places.Redundant information occurs before organization frequently capture and store the same information in multiple locations.The primary problem with redundant information is that it is often inconsistent,which makes it difficult to determine which values are the most current or most accurate.Eliminating information redundancy saves spaces,makes performing information updates easier and improves information quality.

INCREASED INFORMATION INTEGRITY(QUALITY)

-  Information Integrity is a measure of the quality of information.Within a database environment integrity constraints are rules that help ensure the quality of information.

Relational integrity constraint – rule that enforces basic and fundamental information-based constraints. For example an operational integrity constraint would not allow someone to create an order for a none existent customer, provide a markup percentage that was negative ,or order zero pounds of raw material from a suppliers

.Business-critical integrity constraint –rule that enforce business rules vital to an organization’s success and often require more insight and knowledge than relational integrity constraints. Consider a supplier of fresh produce to large grocery chains such as Kroger.

INCREASED INFORMATION SECURITY

•      Information is an organizational asset and must be protected from unauthorized users or misuse.As systems become increasingly complex and more available over the internet,security becomes an even bigger issue.

•          Databases offer several security features including:

–      Password – provides authentication of the user who is gaining access to the system.

–      Access level – determines who has access to the different types of information and access controls determine what type of access they have to information. For example customer services representatives might need read only access to customer order information so they can answer customer order inquiries,they might not have or need the authority to change or delete order information.

3. DEFINE A DATABASE MANAGEMENT  SYSTEM AND ITS RELATIONSHIP TO A WEBSITE?

                           A database management system is used to access information from a      database. A database management system(DBMs) is software through which users and application programs interact with a database. Database management system is a set of programs that enables you to store, modify, and extract information from a database also provides users with tools to add, delete, access, modify, and analyze data stored in one location. The user send requests to the DBMS and the DBMS performs the actual manipulation of the information in the database. Many DBMS also include a graphics component that enables you to output information in the form of graphs and charts. Database and database management system are essential to all areas of business, they must be carefully managed.Consider for example, a company selling sports cars. A database is created with information on each of its currently available cars e.g. make, model, engine details, year, a photograph, etc. A visitor to the website clicks on Porsche, the visitor enters the price range that they are interested in and hits 'Go'. The visitor is presented with information on available Porsche cars in their price range and an invitation to purchase or request more information from the company. The company has the ability to add new cars to the database, remove them or modify existing entries this is achieved via a secure administration area on the website.

EXPLAIN WHY AN ORGANIZATION WOULD WANT TO INTEGRATE ITS DATABASE?

          Data integration refers to the organization’s inventory of data and information assets as well as the tools, strategies and philosophies by which fragmented data assets are aligned to support business goals.The company want to integrate its database because they will connect,communicate,dealing and having relation with its customer everyday. Everyday its customers will open the webpage and search anything appear on the page. Therefore, if the product still available or not available the supplier must inform the customers immediately.Publish the information on the web page to make the customers realize that the product exist or not in the market. Then, when the customers got information they will not too disappointed and not waiting too long. Customers satisfy, the business relationship between sellers and customers will be effective and launch smoothly.