1. Introduction to Database Systems
Lecture #1
Dated: 19-10-2007

2.  Classes: 01:30 PM – 03:00 PM Thursday
11:30 AM – 01:00 PM Friday
 Instructor: Nauman Riaz Chaudhry
 Cell: 0300-9503200
 Email: nauman.riaz@gmail.com

3. Course Overview
 Background and History
 Data Models
 E/R Model
 Relational Model
 Object Oriented Model
 XML and Database
 Database Programming
 Relational Algebra
 SQL
 Object Oriented

4. Textbook
 C. J. Date “An Introduction to Database Systems
”, Seventh Edition, Pearson Education
 Jeffrey D. Ullman and Jennifer Widom, “A First Course
in Database Systems”, Second Edition, Prentice Hall,
2001
 Other useful textbooks:
 Fundamentals of Database Systems (Elmasri and Navathe)
 Database System Concepts (Abraham Siberschatz, Henry
F.Korth and S.Sudarshan)
 Database Management Systems (Ramakrishnan)

5. Tentative Schedule
 Introduction (1-2 classes)
 E/R Model (2-3 classes)
 Relational Model (3-4 classes)
 Other Models (2-3 classes)
 Relational Algebra (3-4 classes)
 SQL (4-5 classes)
 Constraints and triggers (1-2 classes)
 System Aspects of SQL (3-4 classes)
 XML (3-4 classes)

6. Course Load
 3 - 5 homework assignments
 1 project
 5 Quiz's
 A Midterm Exam
 A Final Exam
Homework and project assignments are due in the
beginning of class one or two weeks that follows. Late
homework will not be accepted, and a score of
zero will be assigned for that assignment.

7. Course Policy
 exams: no access to any material nor discussion with
anyone (except the instructor) is allowed.
 assignments: solutions should be developed
independently. Stealing, giving or receiving any code
drawings, diagrams, text, or designs from another
person is not allowed.
 max penalty for academic dishonesty: F in the
course; reported to the university.

8. Grading Policy
 The grade will be calculated using the following
weights:
Homework and Quizzes 15%
Project 10%
Mid-term Exams 25%
Final Exam 50%

9.  Starting from now …
Something completely different!

10. What is Database?
 Essentially, a database is a set of data, or a
collection of information. These data are
related.
 Examples:
Student Information
human genome sequence
company products information

11. More Examples
 Airline Reservation Systems
 Reservations by a single customer on a single flight,
including such information as assigned seat or meal
preference
 Information about the flight, the airports thy fly from and to,
the departure and arrival times, etc.
 Ticket prices, requirements, and availability
 Banking Systems
 Customers, accounts, loans and the balances
 Deposit or withdraw money

12. What’s DBMS?
 DataBase Management System (DBMS)
A powerful tool for creating and manage large
amounts of data efficiently and allowing it to persist
over long periods of time, safely. It also provides
efficient accesses to multiple users.
It is used to manage databases.

13. DBMS capabilities
 Persistent Storage
 Programming Interface
 Transaction management

14. DBMS capabilities (Cont.)
 Allow users to create databases and specify their
schema, using data-definition language.
 Allow users to query and modify the data, using data-
manipulation language.
 Support the storage of very large amount of data over
a long period.
 Data consistency and failure recovery.

15. File System
 Why not using file system?
 Can be used to store data information for a long period as
well.
 Consistency and failure recovery capability
 Problems:
 no query language, no efficient access for a data item
 support of the creation of database is limited
 consistency control is not adequate
Management of Data is complex

16. DBMS Evolution
 File Systems
 Hierarchical Model (Tree-based)
 Network Model (Graph-based)
 Relational Model
 Object Oriented Model
 Object/Relational Model

17. Relational Database System
 Ted Codd 1970
 The view of data: relations
relations, tuples, attributes
tables, rows, columns
 Queries could be expressed in high level
language, it is simple and efficient
 It is widely used in most commercial systems

18. Example 1.1
AccountNo Balance Type
12345 1000.00 Savings
67890 2846.92 checking
… … …
Bank Account Information
(Accounts)

19. Example 1.1 (Cont.)
 Check the balance
SELECT balance
FROM Accounts
WHERE accountNo= 67890
 Check the accountNo
SELECT accountNo
From Accounts
WHERE type=‘savings’ AND balance < 0

20. Major DBMS Products
 Oracle
 IBM: DB2, Informix
 Microsoft: SQL Server, Access
 Sybase
 MySQL
 Postgres
All are "relational" (or "object-relational") database
systems at their core.

21. Schema versus data
 Schema describes how data is to be
structured - defined at set-up time, rarely
changes (part of the "metadata")
 Data is actual "instance" of database, may
change rapidly
 Comparable to types and variables in
programming languages

22. Data Definition Language
(DDL)
 Commands for setting up schema of
database
 Process of designing schema can be
complex, may use design methodology
and/or tool

23. Data Manipulation Language
(DML)
 Commands to manipulate data in database:
RETRIEVE, INSERT, DELETE, MODIFY
 Also called "query language"

24. People
 DBMS implementer: builds system
 Database designer: establishes schema
 Database administrator: loads data,
keeps whole thing running
 Database user: queries/modifies data

25. DBMS Evolution Trends
 Size
smaller and smaller
using personal computer, similar to applications such as
spreadsheet and word processing
bigger and bigger
terabytes or even petabytes data, using tertiary storage and parallel
computing techniques.
 Architecture
Client-server architecture (Two-Tier)
client database Server
Multi-Tier architecture:
client application server database server

26. DBMS Trends (Cont.)
 Versatile Data type
integers, characters
small storage requirement
videos, audios
large storage requirement
 Integration
Data warehouses, data mining

28. Overview of DBMS
 DDL commands
DBA DDL Complier Execution engine …
 Query Processing
 Answering the query
User Query Compiler Execution engine …
 Transaction processing

29. Storage and Buffer Management
 Buffer manager
 Storage manager
 Data: the contents of the database
 Metadata (Schema) : structure of the database
 Statistics: data properties
 Indexes

30. Transaction Processing
 Transaction manager
 Logging
 Concurrency control
 Deadlock resolution

31. Query Processor
 Query complier
 Query parser
 Query preprocessor
 Query optimizer
 Execution engine

32. Outline of Database System
 Database design
Determine the database structure
 Database programming
Perform database operations
 Database system implementation
Build the database

33. Next Class
 E/R Concepts