Bases de Dades: introduction and organization

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1 Andrew D. Bagdanov Departamento de Ciencias de la Computación Universidad Autónoma de Barcelona Fall, 2010

2 Outline

3 Contact information Professor Database systems Important contact info: Name: Dr. Andrew D. Bagdanov Phone: Office: Room 246 Office hours: Tuesdays, 12:00 13:00 and 16:00 17:00 Web: Note: is by far the best way of contacting me. Please prepend BDD: to the subject of your s so I can sort them automatically.

4 Why is he talking funny? Professor Database systems Originally from United States. Lived in Holland, Italy, Spain... Native English speaker. Fluent Dutch and Italian speaker. Worked in universities, state, local and international organizations, wrote video games for Westwood Studios. Currently research fellow in computer vision. A lot of experience in all varieties of IT.

5 Lectures and opportunities Professor Database systems Slides, exercises written in English. Lectures in Spanish, explanations and interactions with you in Spanish. Opportunity to interact and improve English with native speaker. One extra point for doing this in final grade.

6 Philosophy Professor Database systems We re all in it together. Together we are stronger. Tell me a bit about yourselves...

7 What is a database? Professor Database systems Anyone? Protocol for formal specification of data. Data and relationships between data. Allows fast storage and retrieval A Database Management System (DBMS) is: a collection of interrelated data. a set of programs to access the data. a system containing information about a particular (aspect of) an enterprise. an environment that is both convenient and efficient to use.

8 What is a database? Professor Database systems Anyone? Protocol for formal specification of data. Data and relationships between data. Allows fast storage and retrieval A Database Management System (DBMS) is: a collection of interrelated data. a set of programs to access the data. a system containing information about a particular (aspect of) an enterprise. an environment that is both convenient and efficient to use.

9 DBMS Professor Database systems Database management systems were developed to handle the following difficulties of typical file-processing systems supported by conventional operating systems: Data redundancy and inconsistency Difficulty in accessing data Data isolation - multiple files and formats Integrity problems Atomicity of updates Concurrent access by multiple users Security problems

10 What are DBMS-es used for? Professor Database systems Databases have become ubiquitous in modern software systems. Databases are use in: Webapps Desktop systems The Enterprise Embedded applications (iphone, Android) Web browsers Mail clients, IM/chat clients High performance computing environments Just about anything...

11 Big iron systems Out from The Enterprise The scene today DBMS were once associated with big iron. As we saw before, this is no longer the case. As recently as one year ago, courses taught using the Oracle DBMS. Oracle (and their ilk) still have lion s share of market. Especially in The Enterprise. But that sort of depends on how you count.

12 Open source databases growing Out from The Enterprise The scene today Market Update: Open Source Databases Open Source Databases Remain A Viable Choice For Business Applications, Noel Yuhanna with Mike Gilpin, Catherine Salzinger, 2008

13 The times they are a changing Out from The Enterprise The scene today Today, only fraction of DBs in use are Oracle The diffusion of Windows on the desktop resulted in a proliferation of ad hoc DBMS like MS Access. In the open source world: MySQL, Postgres, sqlite, couchdb, etc. In this course we will take a serious look at two (maybe three) systems: sqlite3: an embedded DBMS used in mobile applications, embedded systems and to support desktop apps. MySQL: an enterprise-grade DBMS server. (maybe) couchdb: or another NOSQL-type DBMS.

14 Having fun! What we will be doing What, revisited A note on working in groups What is required of you No, really... Databases are rather simple, once you get them. But getting them requires a lot of hands-on experimentation. Play, really. A lot of what DBMS developers, analysts and administrators do could be called archaeology. Advice: take it easy, and have fun.

15 What, revisited... What we will be doing What, revisited A note on working in groups What is required of you What we will be doing in these problem and practicum sessions is: Working with several types of database systems (MySQL, sqlite3, and maybe a NOSQL database). Learning the purposes and uses of database systems Learning about the relational modeling language SQL (majority of this part of the class, really) Executing a serious project involving databases (in practicum sessions).

16 The database triad What we will be doing What, revisited A note on working in groups What is required of you When working with DBMS, there are three basic roles. But it is important to be able to wear all hats, as often all three roles are performed by one person: DB Designer: responsible for the modeling of the data in an application or system. DB Application Developer: the person responsible for implementing the application or system. DB Administrator: the person responsible for ensuring the continued, healthy operation of the DB system. DB applications usually go through a cycle of Design, Implementation, Administration, Design, etc.

17 Groups, ringleaders and copying What we will be doing What, revisited A note on working in groups What is required of you Communicating, working together is good (together we are stronger). But, everyone, and each practicum group must submit their own work. Talk amongst yourselves, but work problems on own in the end. Even if you work in groups and agree on how to solve a problem, make sure you write up your own solution. Exact copies of assignments will receive a 0. Like all rules, there are exceptions: but arrange it with me first.

18 Problem sessions What we will be doing What, revisited A note on working in groups What is required of you One per week, attendance strongly recommended. Each week, three or four exercises to complete for next week. These should exercises should be prepared for discussion the following week. About fifteen (15) of these will be collected and graded during semester. We will let you know which are the graded problems, and when they will be collected. These problems must be completed and submitted individually. These grades will form your problem session grade for the semester.

19 Practicum sessions What we will be doing What, revisited A note on working in groups What is required of you You will also be required to complete a practicum in which you develop the idea, design and implementation of a non-trivial database system. We will help guide you in designing the application through a series of ten (10) practicum sessions. The practicum will be completed in teams of two people. Schedule for practicum sessions will change slightly. Watch the virtual campus for information.

20 Old roles, new roles Databases in practice For next week DBMS allow formal, code-agnostic representation and persistence of data. They are (mostly) platform independent. Today they are completely ubiquitous. A basic understanding of them is necessary for almost any IT role in the future. For the rest of you career, important to understand how they developed, how they are used today, and how they will evolve.

21 Next time on bases de dades... Databases in practice For next week Please, have a look at the website: In particular, look at the Tools section of the website in preparation getting to work with real DBMS. Be thinking about your practicum projects. Prepare today s exercises...

22 : lecture 1 A few exercises to do at home. Please come to the next problem session prepared to discuss your findings: 1 DB archaeology: Repeat my locate *.sqlite experiment on your (or a university) computer. Try to find more examples of embedded databases in applications. Other things you might search for are *.sql or *.db. 2 Changing times: I mentioned nosql databases a few times, but never said what that means. Do some searching to discover what the principal ideas are behind the nosql movement.