1. Introduction to Database Management Systems

2. Information Instructor: Csilla Farkas
Office: Storey Innovation Center, RM 2253
Office Hours: T, R 10:30 – 11:30 am, electronically, or by appointment
Telephone:
Class homepage:
Farkas
CSCE 520

3. Teaching Assistants
1. Tieming Geng: a. Office hours: b. Office location: Storey Innovation Ctr., room Theppatorn Rhujittawiwat:
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CSCE 520

4. Prerequisite CSCE 245 (CSCE 240, EECE 352) or GEOG 563 or
Permission of the instructor
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CSCE 520

5. Text books
J. D. Ullman and J. Widom: A First Course in Database Systems, 3rd edition, Prentice Hall, ISBN: X
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CSCE 520

6. Grading
Midterm 1: 25%, Final: 35%, Quizzes: 5%, Homework assignments: 35%
Total score that can be achieved: 100
Final grade:
90 < A , 85 < B+ <=90, 80 < B <= 85, 75 < C+ <= 80, 65 < C <= 75, 60 < D+ <= 65, 50 < D <= 60, F <= 50
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CSCE 520

7. Course Policies Code of Student Academic Responsibility Incompletes
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CSCE 520

8. Questions?

9. Chapter 1: Introduction
Evolution of Database Management Systems
Overview of Database Management Systems
Database-System Design
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CSCE 520

10. Database Management System (DBMS)
Databases touch all aspects of our lives
DBMS:
Collection of interrelated data
Set of programs to access the data
Convenient and efficient processing of data
Database Applications
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CSCE 520

11. Evolution of Database Systems
Early days: database applications built on top of file systems
Drawbacks of using file systems to store data:
Data redundancy and inconsistency
Difficulty in accessing data
Atomicity of updates
Concurrency control
Security
Data isolation — multiple files and formats
Integrity problems
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CSCE 520

12. Abstraction
View level: application programs hide details of data types.
Logical level: What is the data?
type employee = record name : string; address : string; salary: real; end;
Physical level: How the data is stored?
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CSCE 520

13. Data Models A collection of tools for describing Data
Relationships among data items
Semantics of stored data
Database constraints
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CSCE 520

14. Data Models Entity-Relationship model Relational model Other models:
Network
Hierarchical
Object-oriented
Semi-structured
Steaming data
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CSCE 520

15. Database Management Systems
Smaller and smaller systems
Past: large and expensive DBMS
Present: DBMS in most personal computers
More and more data stored
Past: few MB
Present: terabyte (1012 bytes), petabyte (1015 bytes)
Data Tsunami
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CSCE 520

16. Database Users
Users are differentiated by the way they interact with the system
Database Administration: responsible for the structure or schema of the database (DDL), coordinates all activities regarding the database
Application programmers – interact with system through DML calls
Sophisticated users – form requests in a database query language
Naive users – invoke one of the permanent application programs that have been written previously
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CSCE 520

17. Data Definition Language (DDL)
Defines the database schema and constraints
DDL compiler  data dictionary
Metadata – data about data
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CSCE 520

18. Data Manipulation Language (DML)
Accessing and manipulating the data
DML – query language
Query Languages
Procedural – user specifies what data is required and how to get those data
Nonprocedural – user specifies what data is required without specifying how to get those data
SQL: nonprocedural query language
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CSCE 520

19. Transaction Management
Transaction: unit of work to be executed atomically and in isolation from other transactions
Transaction-manager: ensures that the database remains in a consistent
system failures
transaction failures
Concurrency-control: interaction among the concurrent transactions to ensure consistency
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CSCE 520

20. ACID Properties
Atomicity: all-or-nothing of the transaction’s effect will take place
Consistency: each transaction leaves the system in a consistent state
Isolation: each transaction must appear to be executed as if no other transactions are executed at the same time
Durability: effect of a transaction must never be lost after the transaction is completed
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CSCE 520

21. Transaction Processing
Logging:
Log manager
Recovery manager
Concurrency control
Multiple transactions
Locking protocols
Deadlock resolution
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CSCE 520

22. Database System Studies
Design of the database
What to store, structure, semantics
Functionality requirement
Trade offs
Security
Database programming
How to express database operations, capability requirements, etc.
Database implementation
Query, transaction processing, storage, efficiency
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CSCE 520

23. Next Class: Relational Database Modeling
A First Course: Chapter 2 (2.1, 2.2, 2.3)
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CSCE 520