Database Management

Managerial Overview

Managing Data Resources

• Data are a vital organizational resource that need to be managed like other important business assets.

• Most organizations could not survive or succeed without quality data about their internal operations and external environment.

Foundation Data Concepts

Data may be logically organized in IS just as writingcan be organized

Character Letter

Field Word

Record Sentence

File Paragraph

Database Document

Personnel Database Example

Employee Personal Data FileFields Name SS No. DomicileEmployeeRecord 1

Jones T. A. 275-32-3874 Livingstone

EmployeeRecord 2

Alvarez J. S. 542-40-3718 Deadpoint

Payroll FileFields SS No. SalaryEmployeeRecord 1

275-32-3874 25.000

EmployeeRecord 2

542-40-3718 40.000

The Database Management Approach

• consolidates data records and objects into databases that can be accessed by many different application programs

• a special software package called a database management system (DBMS) serves as a software interface between users and databases

The Database Management Approachinvolves three basic activities:

• updating and maintaining common databases to reflect new business transactions and other events

• providing information needed for each end user‘s application by using application programs that share the data in common databases

• providing an inquiry/response and reporting capability through a DBMS package so that end users can easily interrogate databases, generate reports, and receive quick responsesto their ad hoc requests for information

The Database Management Approach

InquiryCustomer Transaction Processing

Checking Account Program

Savings Account Program

Installment Loan

Program

Database Management System

Customer Database

Major Uses of DBMS

• Database Development– Database Administrator– Data Dictionary

• Database Interrogation– Query Language (SQL, QBE)– Graphical and Natural Queries– Report Generator

• Database Management

• Application Development

Types of Databases

• Operational Databases– transaction databases, production databases

• Analytical Databases– management databases, information

databases (accessed by OLAP, DSS, EIS)

• Data Warehouses– data marts, data mining

• Distributed Databases• End User Databases• External Databases

Hypermedia Databases on the Web

WebBrowser

Client PCs or NCs

The InternetIntranetsExtranets

Network Server HypermediaDatabase

Webserver

software

HTML pagesGIF image files

Video files

Benefits of Database Management

• DM reduces the duplication of data• DM integrates data so that they can be

accessed by multiple programs and users• Application programs are not dependent on the

format of the data and the type of secondary storage being used

• Inquiry/response and reporting capability allows users to easily obtain information they need

• Computer programming is simplified• Integrity and security of the data can be

increased since access to data and modification of the database are controlled by DBMS, a data dictionary, and a database administrator function

Limitations of Database Management• Limitations arise from the increased technological

complexity of DM• Developing large databases of complex data types and

installing a DBMS can be difficult and expensive• Storage requirements for the organization‘s data

overhead control data, and the DBMS programs are increased

• Longer processing times may result from high-volume transaction processing applications since an extra layer of SW (DBMS) exists between application programs and the operating system

• Vulnerability to errors, fraud, and failures is increased in centralized databases

• Problems of inconsistency of data can easily arise in distributed databases