Chapter 1

Databases Introduction

The content 1).Database Application

2).Database concept

3).An example of database

4).Function of DBMS

5).DBMS product Difficulty: the function of DBMS

Focus on: the concept of DBMS

Hours:2 hours

Teaching way: ppt

Database Application

Databases touch all aspects of our lives Banking: all transactions Airlines: reservations, schedules Universities: registration, grades Sales: customers, products, purchases Online retailers: order tracking, customized

recommendations Manufacturing: production, inventory, orders, supply chain Human resources: employee records, salaries, tax

deductions

Database concept

1) Data Used to describe the world. can be recorded and have implicit meaning. Data can exist in a variety of forms -- as numerical

numbers, letters, text, image, sound, video and etc.

Data can be stored ,processed, transmitted. Example:

（ Tom，male， 1992， Chang Sha， computer specialty， 2010）

Database concept

2) Database it’s nothing more than a collection of related data

that exists over a long period of time.

Student table index name age gender major year

95004 Lily 19 f computer

95

95006 Tom 20 m medicine

95

95008 Lucy 18 f law 95

… … … … … …

Example of Data and Database

Sizes of Database Personal database

1 user; < 10 MB Workgroup database

< 25 users; < 100 MB Organizational database

Hundreds to thousands users >1 Trillion bytes, possibly several databases

Database concept

3) DBMS A collection of programs that enables you to store,

modify, protect,manage and extract information from a database.

There are many different types of DBMSs, ranging from small systems that run on personal computers to huge systems that run on mainframes.

DBMS functionality

Definition Define a database involves defining the data types, structur

es, and constraints for the data to be stored in the database.

Manipulation Manipulating a database includes such functionsas querying the database to retrieve specific data, updating th

e database to reflect changes in the miniworld

Sharing Sharing a database allowsmultiple users and programs to access the database concurre

ntly.

DBMS functionality

Protection includes both system protection

against hardware or software malfunction (or crashes), and security protection against

unauthorized or malicious access.

Maintenance

Such as inputting and transferring of Data, DB backup and recovery, performance monitoring, audit and analysis etc.

Database System (DBS) 4) Database System (DBS).

DB, DBMS, Development Tools, DB applications, DB Administrator (DBA) and users

DB

OS

DBMS

Developing Tools

DB applications

User User

DBA Hardware

Operating System

DBMS, Compiling System

Developing Tools

Application Systems

DBMS in Computer System

A simplified database system environment.

A specific example A database that stores

student and course information.

A specific example A database that stores

student and course information.

A specific example A database that stores

student and course information.

A specific example Two views derived from the database

in Figure (a) The STUDENT TRANSCRIPT view. (b) The COURSE

PREREQUISITES view.

3 DBMS Product VFP、ACCESS

MYSQL、HOSTSQL

ORACLE

SQL SERVER

SYSBASE

INFORMIX

INGRES

DB2

OS DOS

WIN98

Linux all windows

all all all AS/400

company

MS ORACLE

MS SYSBASE

informix

IBM

time 80’s 90’s 1979 1994 1987 1988 1975

capacity

usual usual good good good good good good

The DBMS Marketplace Relational DBMS companies – Oracle, SybaseOracle, Sybase – are among the larg

est software companies in the world. IBM offers its relational DB2DB2 system. With IMS, a nonrelational syste

m, IBM is by some accounts the largest DBMS vendor in the world. Microsoft offers SQL-ServerSQL-Server, plus Microsoft AccessMicrosoft Access for the cheap DB

MS on the desktop, answered by “lite” systems from other competitors.

Relational companies also challenged by “object-oriented DB” companies.

But countered with “object-relational” systems, which retain the relational core while allowing type extension as in OO systems.

Summary

From this lecture you can learn the basic concept of database such as DB,DBS,DBMS and the differences between them ,the function of DBMS and the history of data processing and via an example you can master these concept better.

Any Questions?If there are any outstanding questions you can ask me one-to-one after the lecture OR privately in my office.

Exercises

What are the definitions of data ,DB,DBMS,DBS,DBA?

Go to search the internet and find out the tendency of database.

Learn MS Access by yourself.