database systems i - datenbanksysteme tübingen...

Database Systems IFoundations of Databases

Summer term 2010

Melanie [email protected]

Database Systems Group, University of Tübingen

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Foundations of Databases | Summer term 2010 Melanie Herschel | University of Tübingen

Chapter 0Overview

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• Overview

• Administrativa

• A little bit of History

Credit: Michael Marcolhttp://www.freedigitalphotos.net/images/view_photog.php?photogid=371

Foundations of Databases | Summer term 2010 | Melanie Herschel | University of Tübingen

Welcome Everyone!

Grew up in Bavaria & Lorraine

2000 - 2003Student at the University of Cooperative Education StuttgartInformation Technology

2003 - 2007Research Assistant at Humboldt University in Berlin & at the Hasso-Plattner-Institute PotsdamData quality & data integration

2007 PhD defense

2008 - 2009Post-Doc researcher at the IBM Almaden Research CenterData provenance / query understanding

since 06/2009Research assistant at Tübingen University“Debugging” queries with Nautilus

First of all, let me introduce myself...

Melanie Herschel

B315, Sand 13

Tel +49 7071 29-75481

Email melanie.herschel@uni - tuebingen.de

Web ht tp://www-db.informatik .uni - tuebingen.de/team/herschel

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Welcome Everyone!

... and now it is your turn.

Bachelor vs. Diplom?

Computer science, bioinformatics, other studies?

Prior experience with databases?

locals or “neigscheckte”?

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Which semester?


Where to Meet Databases

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What is this course about?

• Convince you that there is more to database technology than just open-file(), read()/write(), and close-file().

• Make you see how versatile the strictly tabular data model supported by relational databases can be.

• Make you best friends with SQL, the principal language spoken by relational database systems.

• We will encounter a healthy mix of good, clean theory and highly relevant CS practice.

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What is this course about?Structure

1. Introduction2. ER-Modeling3. Relational model(ing)4. Relational algebra5. SQL6. Programming

• What are databases?

‣ Motivation, history, data independence, database usage

• Modeling databases using the Entity-Relationship Model

‣ Entities, relationships, cardinalities, diagrams

• Developing relational databases

‣ Relational model, ER -> relational, normal forms

• Relational algebra

‣ Criteria for query languages, operators

• SQL

‣ SQL DDL, SQL DML, SELECT... FROM... WHERE...

• Programming for databases

‣ JDBC

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What is this course about?ER-Modeling


ownsCustomer Account

Firstname Lastname DOB Number Type Balance

1,1 1,n

• We want to model customers and their accounts(saving account, checking account, credit card, ...)

• Customers and accounts have attributes, e.g., a person has a firstname, lastname, and date of birth.

• A customer can have one or more accounts.

• We assume that an account can only have one owner.

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What is this course about?Relational Model


ownsCustomer Account

Firstname Lastname DOB Number Type Balance

1,1 1,n

Cust_ID Firstname Lastname DOBCustomer

Number Type Balance Cust_IDAccount

CREATE TABLE Account (Number INTEGER,Type CHAR(25),Balance DOUBLE,Cust_ID INTEGER,PRIMARY KEY (Number),FOREIGN KEY Cust_ID

REFERENCES Customer) 10


What is this course about?Relational Model


Cust_ID Firstname Lastname DOB1 John Doe 1.1.1970

2 Jane Smith 2.2.1977

4 Peter Miller 3.3.1983

... ... ... ...

Customer

Number Type Balance Cust_ID123 Checking 2000 1

124 Saving 5000 1

987 Checking 100 2

975 Credit 500 2

777 Saving 6000 4

... ... ... ...

Account

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What is this course about?Relational Algebra & SQL


Declarative queries

• Not “How do I generate the query result?”

• But “What data does the query result contain?”

Natural language query

Name of account owner and account number of all accounts with a balance of more than 1000 Euros.

Relational Algebra

πlastname,number (σbalance > 1000 ( σc.cust_id = a.cust_id (customer × account))

SQL

SELECT c.lastname, a.number FROM Customer c, Account a WHERE a.balance > 1000 AND a.cust_id = c.cust_id

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What is this course about?Programming (if time permits)


• Accessing the database from an external program

• For instance, from a JAVA program, we can communicate with a database via JDBC.

‣ JDBC Driver

‣ Open Connection

‣ Querying the database

‣ Processing query results

...ResultSet r = statement.executeQuery(myQueryString);

while (r.next()) { String lastname = r.getString(1); String accountNumber = r.getInt(2); Address a = getAddress(lastname, accountNumber); initCommercial(a);} 13


Chapter 0Overview

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• Overview

• Administrativa



AdministrativaCourse schedule

LecturesWhen? Where?

Monday, 10:15 - 11:45 Sand 6/7 kleiner Hörsaal

Tuesday, 10:15 - 11:45 Sand 6/7 großer Hörsaal

PracticalsWhen? Where?

Thursday, 14:15 - 15:45 Sand 13, A104

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• First assignment available on April 15, 2010.

• First assignment will be discussed April 22, 2010.


AdministrativaKeep up to date

http://www-db.informatik.uni-tuebingen.de/teaching/ss10/db1Please visit regularly, as the latest slides and news will be posted there.

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http://twitter.com/DBatUTuebingenStay tuned to the latest database group news.

https://cis.informatik.uni-tuebingen.de/db1-ss-10/Register in order to view assignments and access your scores.


AdministrativaEvaluating your Performance

End-term exam

• 90 mins. examination on Monday, July 12th, from 10:15 - 11:45.

• No supplemental material is allowed.

• Passing earns you 6 ECTS.

Assignments and grading

• We will distribute, collect, and grade weekly assignments.

• Assignments will be available on our website or via CIS.

• You have one week to complete each assignment.

• You may - and you should - work in teams of two.

• You should hand in your assignments in paper form at Manuel Mayr’s office.

• Scoring 2/3 of the overall points in the assignments earns you an additional 2 ECTS.

• Your scores will be available via CIS only. 17


These slides...

Quizzies Definition

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Code snippetsExamples


Read a book, write some SQL

Any introductory book is fine, two suggestions are

•Raghu Ramakrishnan and Johannes Gehrke.Database Management Systems. McGraw-Hill.(Vorlesung ist stark an diesem Buch orientiert)

•Alfons Kemper and André Eickler.Datenbanksysteme: Eine Einführung. Oldenbourg Verlag

Install IBM DB2 V9.5 Express-C

•We will bring it with us for almost any lecture.

Dowload at http://www-01.ibm.com/software/data/db2/express/

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Further literature!"#$"%"&'#$"%($)%!"#$"%"&'#$"%($)%

!"

!"#$%"& '"(")"*+ ,"$-.

*"+#,&-().(//&0&1'&2($"/3(/4565$"."&7&0&89.."%&:;;<

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Questions and Feedback

• Questions anytime!

• During the lecture

• In dedicated office hour: Monday, 15:00 - 16:00

• Email, phone

• Feedback and suggestions are highly appreciated

• Slides

• Information on the Website

• ...

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Before we get started...... Commercials

Studien- / Bachelor- / Diplom- / Masterarbeitenhttp://www-db.informatik.uni-tuebingen.de/teaching/studentische-arbeiten

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Selected Fun Problems of the ACM Programming Contest

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Proseminar SS 2010www-db.informatik.uni-tuebingen.de

Vorbesprechung: 15.04.2010, 09:30, B305b


Chapter 0Overview

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• Overview

• Administrativa



A little bit of HistoryData Collection and Storage Technology

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• Herman Hollerith: “punch card tabulating machine”

•Companies (precursors of IBM)

•Tabulating Machine Corp - 1896

•Computing-Tabulating-Recording Company(C-T-R) - 1911

•International Business Machines Corporation (IBM) - 1924

Credit: IBM Archive, Computer History Museum, Mountain View, CA

Computer History Museum, Mountain View, CA


A little bit of HistoryHard-Drive Technology

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• Magnetic Disc Drive: RAMAC 350 by IBM - 1955/56

•“Random Access Method of Accounting and Control”

•Developed in San Jose, CA

•Technical lead: Reynold B. Johnson (1906-1998)

•Since then, HDD development has followedMoore’s Law

•Cost per MB has decreased by half approx. every 18 months.

•The areal density (bits/inch2) has doubledapprox. every 18 months.

Credit: IBM Archive, Computer History Museum, Mountain View, CA


A little bit of HistoryTimeline

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1960 1970 1980 1990 2000

Database systems based on hierarchical model,

network model

Database systems based on the relational model

Scaling database systems to the very large and the very small

Object-oriented databases

Specialization to new types of data


A little bit of HistoryDatabase Systems in The Sixties

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Early 1960s

• Data is stored in files.

•Application dependent organization of the data

•Integrated Data Store (IDS) by General Electric

Late 1960s

•File management systems (SAM, ISAM)

•Basic operations on the data are possible, e.g., sorting

•Information Management System (IMS) by IBM

‣Still in use on mainframes today, with more than 1 Billion $ revenue.


A little bit of HistoryRelational Database Management Systems

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1970s

• Database systems emerge

•Ted Codd (IBM): relational data model as conceptual basis for relational database systems - 1970.

•System R (IBM): first prototype of a relational database management system - 1974

‣Roughly 80,000 lines of code (PL/1, PL/S, Assembler)

‣SEQUEL as a query language

‣First installation in 1977.

•Ingres (University of Berkeley) - 1975

‣QUEL as a query language

‣Precursor of Postgres, Sybase, ...

•Oracel Version 2 - 1979


A little bit of HistoryRelational Database Management Systems

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Credit: Prof. Freytag, Ringvorlesung 2005


A little bit of HistoryDatabase Development in the 1980s and 1990s

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• Systems become smaller and smaller.

‣DBMS run on smaller hardware.

‣DBMS become part of standard installations.

•Systems process more and more data.

‣Gigabyte, Terabyte

‣Large and complex (Multimedia-) objects

‣Persistent storage using hard drives and tertiary storage (tapes, DVDs)

‣Distributed and parallel processing

•Object-oriented database systems


A little bit of HistoryDatabase Development in the new Millennium

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• Support for new types of data

‣XML- and semi-structured data

‣Multimedia (Pictures, Audio, Video)

•Federated databases: integrating data from heterogeneous sources (databases, files, web-sources)

•Mobile databases

‣Managing data on handheld devices (PDA, mobile phone, ...)

•Data Warehouses: From transaction processing to analytical processing

•Information retrieval

•Distributed processing

•...

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