Introduction Why Databases? Can you name one application that does - - PDF document

Introduction

CMPT 354: Database I -- Introduction 2

Why Databases?

• Can you name one application that does not

need any data?

– No, a program itself is data

• Can you name one application that does not

need organized data?

– No, “programs = algorithms + data structures”

CMPT 354: Database I -- Introduction 3

Database and DBMS

• Database: a collection of data that (often)

exists over a long period of time

• Database management system (DBMS): a

software designed to assist in maintaining and utilizing large collections of data

– Schema (logical structure of data) specification – Query specification and answering – Storage management – Access control

CMPT 354: Database I -- Introduction 4

Databases or DBMS’s?

• “I just installed SQL Server in my computer”

– DBMS

• “I collected 100 student records, and saved

them in a spreadsheet”

– A database

CMPT 354: Database I -- Introduction 5

What Are Database Courses About?

• How to store, retrieve and analyze (large

amount of) data

• Database applications: how to use

databases?

• DBMS: how to design and implement

efficient database management systems?

CMPT 354: Database I -- Introduction 6

Three-level Architecture

CMPT 354: Database I -- Introduction 7

Levels of Abstraction

• Physical level: describes how a record (e.g.,

customer) is stored (e.g., the block-id and the

• ffset on disk)
• Logical level: describes data stored in database,

and the relationships among the data

– A customer record contains account-id, name, gender, phone number, and address

• View level: application programs hide details of

data types

– A sales application can access name and phone number only

CMPT 354: Database I -- Introduction 8

DBMS

CMPT 354: Database I -- Introduction 9

History: 1950s and Early 1960s

• Data processing using magnetic tapes for

storage

– Tapes provide only sequential access

• Punched cards for input

CMPT 354: Database I -- Introduction 10

History: Late 1960s and 1970s

• Hard disks allow direct access to data
• Network and hierarchical data models in

widespread use

• Ted Codd defines the relational data model

– Codd won the ACM Turing Award for this work – IBM Research began System R prototype – UC Berkeley began Ingres prototype

• High-performance (for the era) transaction

processing

CMPT 354: Database I -- Introduction 11

History: 1980s

• Research relational prototypes evolve into

commercial systems

– SQL becomes industrial standard

• Parallel and distributed database systems
• Object-oriented database systems

CMPT 354: Database I -- Introduction 12

History: 1990s

• Large decision support and data-mining

applications

• Large multi-terabyte data warehouses
• Emergence of Web commerce

CMPT 354: Database I -- Introduction 13

History: 2000s

• XML and XQuery standards
• Automated database administration
• Diversity in data: web data, privacy control,

streaming data, uncertain data, …

CMPT 354: Database I -- Introduction 14

Then, What Is CMPT 354 about?

• Database applications: prepare you for real

world scenarios

– How to store data into databases? – How to retrieve data from databases? – How to design databases for various applications?

• CMPT 454: designing and implementing a

good database management system

• CMPT 459: an in-depth study of data mining

CMPT 354: Database I -- Introduction 15

Topics

• Introduction
• Storing data in relational tables
• Simple SQL
• Advanced SQL
• Database design
• Improving database design for transaction

processing and data analysis

• Inside DBMS: a glance
• Semi-structured data and XML
• Web search and information retrieval

CMPT 354: Database I -- Introduction 16

What Is New in CMPT 354?

• How many of you know SQL and used

databases before?

– Many

• How many of you know the ER model and

the relational model?

– Many

• Then, why should you take this course?

– How to achieve good design for various types of (large) applications? – Go beyond relational databases: XML, web, …

CMPT 354: Database I -- Introduction 17

Highlights – Some Interesting Topics

• If I want to write an online e-business

system, how should I improve my database design?

• If I want to analyze the sales data of a large

company in a multidimensional way, how should I improve my database design?

• How does a search engine like Google and

Yahoo rank web pages?

CMPT 354: Database I -- Introduction 18

Emphases

• Problem solving skills

– Database design – Writing complicated queries

• Practical applications

– Transaction processing systems (e.g., sales system) – Analytical processing systems (e.g., sales analysis systems) – Web-based applications

CMPT 354: Database I -- Introduction 19

Textbook and References

• Silberschatz, Korth and Sudarshan: Database

Systems Concepts, 5th edition, McGraw Hill, 2006

• References

– Lewis Bernstein and Kifer: Database and Transaction Processing: An Application-Oriented Approach, Addison Wesley, 2002. – Garcia-Molina, Ullman and Widom: Database Systems: The Complete Book (Errata), Prentice Hall, 2002. – John. J. Patrick: SQL Fundamentals, 2/E, Prentice Hall, 2002.

CMPT 354: Database I -- Introduction 20

Lecture Notes

• The textbook does not cover all materials in this course, up

to 1/3 of the content is new!

– New materials due to new applications and new techniques – Attending the classes and taking notes is extremely important!

• Exams will be based on the lecture notes

– Notions and terminology in the lecture notes should be followed – The lecture notes will be put on the course web page at least a few hours before the class – Please bring your copy or load them into your laptop and take further notes!!!

• Some figures in my slides are borrowed from the textbook

CMPT 354: Database I -- Introduction 21

Grading Scheme

• Reading and to do list for every lecture (no hand-

in) (100%)

– You need to read the textbook after lectures – To do list helps you to get a better understanding

• 3 assignments (15%)
• One course project (15%)
• 2 one-hour exams (20%, Sept. 28 and Oct. 26,

tentatively)

• Final exam (50%)

CMPT 354: Database I -- Introduction 22

About the Course Project

• It is challenging and interesting

– Group project: 4 students in a group – Build a tablet interface of a database: How to interactively explore data using a tablet PC? – The more creative, the better

• You need to use .NET

– You need to learn the software tools by yourself

CMPT 354: Database I -- Introduction 23

About the To-do Lists

• Help you to review the materials
• Do it by yourself

– Try to solve the problems before looking at the answers – Some solutions are provided

• No pain, no gain

CMPT 354: Database I -- Introduction 24

Expectations

• Strong incentives to learn new knowledge,

not just passing another course

• Come up with new ideas creatively to solve

real world problems

• Work hard to gain solid understanding and

skills

• Team work

CMPT 354: Database I -- Introduction 25

Questions and Suggestions?

CMPT 354: Database I -- Introduction 26

To-Do List

• Name 3 meaningful applications that do not

need a database

• Name 3 meaningful applications that need a

database

• Compare the features of the two groups of

applications