Introduction to Database and DBMS

DATA

• raw, unorganized, unprocessed facts, such as values or measurements

• Can be numbers, words, diagrams, images, observation, or even descriptions of things

• can be captured, recorded, compiled, structured, retrieved, interpreted and stored

INFORMATION 

• reveals the meaning of data

• the purpose is to aid in making decisions and/or solving problems or realizing an opportunity 

• Knowledge is a combination of information 

• When data is processed, organized, structured or presented in a given context to make it useful

EXAMPLE

• Data: 41213

• Information: 4/12/13 is the date of your final software presentation

DATABASE (DB)

• Large, integrated, shared collection of data which will be used to support the activities if particular org

• Can be viewed as a large repository that houses end-user data and metadata

• Inventory

• Accounting

• Hospital/Dental Information

• HR/Personnel Systems

• Payroll Systems - process salaries and benefits

• University Systems

APPLICATIONS OF DB

DATABASE MANAGEMENT SYSTEM (DB)

• Software allows users to interact with DB

• Convenient for user to retrieve and store data

• App sends requests through the DBMS

FACILITIES OF A DBMS

• Define a DB (data types, structures, structures thru DDL)

• Insert, delete, update, retrieve (DML)

• Ex. SQL - formal and defacto language for RDBMS

• Controlled access to DB

• Ex. Provide security system

• Oracle

• IBM (D2)

• MS (MS SQL, Access)

• Sybase (Informix)

• Free (MySQL)

DBMS Industry

FILE-BASED SYSTEM

Collection of apps that perform services to the end users

FILE-BASED SYSTEM APPROACH

• No centralized storage of data

• Each department controls and stores its own data

DB SYSTEM APPROACH

• Having a DB controlled by a DBMS

• Makes DB management more effective in an organization

• Implemented in response to problems in the FB approach

ADVANTAGES OF THE DB SYSTEM APPROACH

• Consistency of data

• Integrity of data

• Sharing

• Centralized data