Introduction to Database Management Systems

Information Instructor: Csilla Farkas Office: Swearingen 3A43 Office Hours: Monday, Wednesday 2:30 pm – 3:30 pm, electronically, or by appointment Telephone: Class homepage: /csce520.htmhttp:// 2013/csce520.htm FarkasCSCE 5202

Prerequisite CSCE 245 (CSCE 240, EECE 352) or GEOG 563 or Permission of the instructor FarkasCSCE 5203

Text books J. D. Ullman and J. Widom: A First Course in Database Systems, 3 rd edition, Prentice Hall, ISBN: X R. Sunderraman: Oracle 10g Programming (or Oracle 10i Programming), A Primer, Addison Wesley Longman, Inc., ISBN: FarkasCSCE 5204

Grading Tests: Test 1: 20%, Test 2: 35% Homework Assignments: 45% – Includes assignments related to the lectures – Includes hands-on database implementation – Includes demo of Oracle implementation Total score: 100 Final grade: 90 < A, 87 < B+ <=90, 80< B <= 87, 77 < C+ <= 80, 68 < C <= 77, 62 < D+ <= 68, 52 < D <= 62, F <= 52 FarkasCSCE 5205

Course Policies Code of Student Academic Responsibility Incompletes FarkasCSCE 5206

APOGEE Students Access recorded lectures Contact instructor via – Phone (during office hours) – – Or any time at a prearranged time Need to attend exams as scheduled Need to arrange for Oracle demo FarkasCSCE 5207

Tentative Schedule Week 1: Introduction Week 2:ER model Week 3:Relational model Week 4:Project overview and Oracle accounts Week 5:Relational Algebra Week 6:SQL Week 7:Relational Design Week 8:Constraints Week 9:Transactions Week 10:Logical query languages Week 11:Data storage and Data representation Week 12:Index structures Week 13:System Failures Week 14:Concurrency control Week 15:Summary and Review FarkasCSCE 5208

Test Schedule Test 1:Early October Test 2: December 9, 4:00 pm FarkasCSCE 5209

Questions?

Chapter 1: Introduction Evolution of Database Management Systems Overview of Database Management Systems Database-System Design FarkasCSCE 52011

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 FarkasCSCE 52012

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 FarkasCSCE 52013

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? FarkasCSCE 52014

Data Models A collection of tools for describing – Data – Relationships among data items – Semantics of stored data – Database constraints FarkasCSCE 52015

Data Models Entity-Relationship model Relational model Other models: – Network – Hierarchical – Object-oriented – Semi-structured – Steaming data FarkasCSCE 52016

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 (10 12 bytes), petabyte (10 15 bytes) FarkasCSCE Data Tsunami

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 FarkasCSCE 52018

Data Definition Language (DDL) Defines the database schema and constraints DDL compiler  data dictionary Metadata – data about data FarkasCSCE 52019

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 FarkasCSCE 52020

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 FarkasCSCE 52021

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 FarkasCSCE 52022

Transaction Processing Logging: – Log manager – Recovery manager Concurrency control – Multiple transactions – Locking protocols Deadlock resolution FarkasCSCE 52023

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 FarkasCSCE 52024

Next Class: Relational Database Modeling A First Course: Chapter 2 (2.1, 2.2, 2.3) FarkasCSCE 52025