Ebook Management Information System: Part 2

Ebook Management Information System: Part 2 presents the following content: future of networking technologies; databases and data warehouses; the wireless revolution; enhancing decision making for the digital firm;...Please refer to the documentation for more details.
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Ebook Management Information System: Part 2 Pooja, Lovely Professional University Unit 8: Databases and Data Warehouses Unit 8: Databases and Data Warehouses Notes CONTENTS Objectives Introduction 8.1 Database 8.2 Traditional vs Database Approach 8.2.1 Files: The Traditional Approach 8.2.2 Database – The Modern Approach 8.3 Database Models 8.3.1 Relational Model 8.3.2 Object-oriented Model 8.3.3 Relational Operations SQL 8.3.4 Data Modelling 8.3.5 Hierarchical Model 8.3.6 Network Model 8.4 Database on the Web 8.4.1 Web Database 8.4.2 Daffodil DB: A Web Database 8.4.3 PHP 8.4.4 PHP and Daffodil DB: Together? 8.5 Data Warehousing 8.5.1 Characteristics of Data Warehouse 8.5.2 What is a Data Warehouse? 8.5.3 Use of Data Warehouses in Organizations 8.5.4 Need to Build a Data Warehouse 8.6 Summary 8.7 Keywords 8.8 Review Questions 8.9 Further Readings Objectives After studying this unit, you will be able to:  Understand the concept of databases  Differentiate between Traditional and Database Approach  Explain Database Model and Relational Model  Discuss Object Oriented Model  Recognize Relational Operations SQL  Understand Data Modelling  Discuss Database on the Web  Explain Data Warehousing LOVELY PROFESSIONAL UNIVERSITY 143 Management Information Systems Notes Introduction Effective use of information depends on how data are stored, organised and accessed in an organisation. Proper delivery of information not only depends upon the capabilities of computer hardware and software but also on the organisation’s ability to manage data as an important resource. After seeing the various methods and approaches of system development, now, let us have some understanding of how important are the data resources in an organisation and how the information system we developed is going to handle them. It has been very difficult for organizations to manage their data effectively. In trying to do so, we have to meet two very big challenges which are standing out. Implementing a database requires a widespread organisational 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 organisational agreement. A database management system (DBMS) challenges the existing power arrangements in an organisation and for that reason often generate 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 organisation has spent the money on hardware and software for a database environment, it may not reap the benefits it should if it is unwilling to make the requisite organisational changes. 8.1 Database A database is a collection of data, which is organized in a way that allows for easy data retrieval and manipulation. While a folder with several files in it may be viewed as a simple database, database professionals usually require that a database have a database management system (DBMS). A DBMS is a software tool, which stores data in a specified form and provides access to this data for a user or an application. Specifically, a DBMS provides some or all of the following functionality: 1. Data Definition: A DBMS must define a structure for stored data, and provide a means for a user to define and organize their data within that structure. 2. Data Retrieval: A DBMS must provide a toolset that allows a user to retrieve data stored in the database (for instance, query tools). 3. Access Control: The database administrator should be able to define data access for an individual or a group. 4. Data Sharing: More than one user should be able to use the database at the same time without a danger of overwriting each other’s data changes. 5. Data Integrity: A DBMS should provide mechanisms for maintaining data integrity through system failures and inconsistent, or incomplete, updates. Self Assessment Fill in the blanks: 1. A .................................. is a collection of data, which is organized in a way that allows for easy data retrieval and manipulation. 2. A DBMS is a .................................. tool, ...