1. Information structures and implications 2015 Prof. Bettina Berendt Thanh Le Van 22 September 2015

2. Most important URL for this course http://people.cs.kuleuven.be/~bettina.berendt/teaching/2015-16-1stsemester/isi/ 2

3. Today Who are we? Course overview and practical things What are data? What is a database? What does this mean for you? Some relevant concepts Introducing our first case study 3

4. Course overview and practical things

5. Lectures 5

6. Exercise sessions Start in week 3 Are an integral part of the course Hands-on experience with data(bases) Detailed plan will follow Direct preparation for the assignments 6

7. Assignments and evaluation Proceed from “exercise-style” to “mini-project” Written and oral (presentation of your results) Are the main basis of evaluation Plus participation in class No exam No second examination chance in September! 7

8. Materials Plus extras: online or distributed otherwise 8

9. Ask questions! In the lecture In the exercise session In the Toledo forum 9

10. 10

11. Today Who are we? Course overview and practical things What are data? What is a database? What does this mean for you? Some relevant concepts Introducing our first case study 11

12. ... and now for the interactive part

13. (Just a reminder of what we did) 1.Introduce your neighbour in terms of data 2.“How else can you describe a person?“ – datafying ourselves 3.Do you use databases? Which ones? How? 4.Other people have similar experiences... “Homebrew Databases“ – Amy Voida, Ellie Harmon, and Ban Al-Ani. 2011. Homebrew databases: complexities of everyday information management in nonprofit organizations. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI '11). ACM, New York, NY, USA, 915-924. – Paper: http://ellieharmon.com/docs/VoidaHarmonAlAni-Homebrew-CHI2011.pdfhttp://ellieharmon.com/docs/VoidaHarmonAlAni-Homebrew-CHI2011.pdf – Talk: http://people.csail.mit.edu/karger/Talks/HomebrewDatabases.pdfhttp://people.csail.mit.edu/karger/Talks/HomebrewDatabases.pdf 13

14. […] it is on account of the grown-ups and their ways. When you tell them that you have made a new friend, they never ask you any questions about essential matters. They never say to you, "What does his voice sound like? What games does he love best? Does he collect butterflies?" Instead, they demand: "How old is he? How many brothers has he? How much does he weigh? How much money does his father make?" Only from these figures do they think they have learned anything about him. If you were to say to the grown-ups: "I saw a beautiful house made of rosy brick, with geraniums in the windows and doves on the roof," they would not be able to get any idea of that house at all. You would have to say to them: "I saw a house that cost $20,000." Then they would exclaim: "Oh, what a pretty house that is!" 14

15. Today Who are we? Course overview and practical things What are data? What is a database? What does this mean for you? Some relevant concepts Introducing our first case study 15

16. Some relevant concepts

17. Databases vs. files Files – Each program defines structure – Several programs: redundancies, or need for transformation Databases – Data + metadata* that describe the structure – Independent of programs * At least in traditional databases 17

18. An example: What should the KU Leuven student database contain? 18

19. 19 Tables, also known as relations, referring to one another  Relational databases

20. 20 An example of metadata of such a database

21. Goals? – Structure – Make accessible – manipulate – Hold consistent – Store “securely” data 21

22. Database A set of centrally managed, permanently stored data, which always have to be available to different applications All data that are relevant for all previewed applications Every application sees/access only relevant data Different applications share the same data 22

23. Some definitions Database system – Database (the data themselves) – Database management system (DBMS) DBMS – Create database structure (“schema”) – Add, delete, modify data – Access / query data 23

24. 24

25. A foretaste … ER 25

26. EMPLOYEE Sex Name Ssn FnameMinitLname Address Bdate Salary DEPARTMENT Number Locations Name PROJECT Name Number Location DEPENDENT NameName Sex BirthDate Relationship WORKS_FOR CONTROLS MANAGES StartDate SUPERVISES HAS_DEP. 1 N 1 1 1 N supervisorsupervisee 1 N 1 N WORKS_ON Hours N M

27. A foretaste … SQL 27 SELECT DISTINCT Pnumber FROMPROJECT WHERE Pnumber IN (SELECT Pnumber FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE Dnum=Dnumber AND …) OR Pnumber IN (SELECT Pnumber FROM … WHERE …) ;

28. Today Who are we? Course overview and practical things What are data? What is a database? What does this mean for you? Some relevant concepts Introducing our first case study 28

29. Exercise for next session 29 1.Read the European Parliament texts that are hyperlinked on the course page 2.Think of a (small) research question you could have from the perspective of your discipline – or another one 3.Model the data that you would need to answer it with “boxes, bubbles and diamonds”

30. 30