Introduccion a rdb o oodb

Solo disponible en BuenasTareas
  • Páginas : 30 (7310 palabras )
  • Descarga(s) : 0
  • Publicado : 29 de abril de 2011
Leer documento completo
Vista previa del texto
A Gentle Introduction to Relational and Object Oriented Databases

Frank Stajano
http://www.orl.co.uk/~fms/ fstajano@orl.co.uk

ORL Technical Report TR-98-2

(Blank even-numbered page so that “chapters” start on an odd page when printing double-sided.)

Preface
In late 1995 I was part of a workgroup that was about to embark on a new project that would eventually use a largedatabase. The people in the group came from different backgrounds and experiences and so, to ensure that we could all agree on basic concepts and terminology, I volunteered to prepare a talk explaining the fundamentals of relational databases, a favourite topic of mine. The talk was very well received, so I was given the job to find out about object oriented databases and to report on that as well. Ispent about a month in the library doing a literature survey, at the end of which I compiled an annotated bibliography and presented a second talk. I made this material available on my web space and then, after a few months, forgot about it. I even ended up archiving it away to CD when I was running low on disc quota. Only recently, thanks to some flattering fan mail, did I realise that mypresentations were actually being used around the world in university lectures from Austria to Australia. So, to make them visible to a wider audience, I am now collecting them in an ORL technical report, which is what I should have originally done. This report is an exact reproduction1 of my 1995 material. It consists of three parts: a talk on relational databases, a talk on object oriented databasesand a commented bibliography on object oriented databases. The talks are intended as onehour introductions for an audience of computer professionals, assumed to be technically competent but not familiar with the topics discussed. No prior knowledge of databases is assumed for the relational database talk, and having absorbed the first talk is a sufficient precondition for understanding thesecond. Knowing from experience that slides often feel bare when reprinted, I have augmented them with comments echoing what you would have heard from me if you had been present at the talk. If you wish to use or adapt these talks as your own training material, which you are free to do as long as you credit the source and give a pointer to my page, the corresponding Powerpoint presentations arefreely downloadable from http://www.orl.co.uk/~fms/db/. Since I am now working on other subjects, I have no plans to keep the bibliography up to date. However I hope that you’ll find this material useful as an introduction and welcome any feedback. Cambridge, UK May 1998

Note that, since then, our domain name has changed from cam-orl.co.uk to simply orl.co.uk, and the name of our laboratory haschanged from Olivetti Research Limited to the Olivetti & Oracle Research Laboratory, which we pretend still fits into the ORL acronym.

1

(Blank even-numbered page so that “chapters” start on an odd page when printing double-sided.)

An introduction to relational databases
Frank Stajano
Olivetti Research Limited

1

This is a short introduction to the topic of relational databases.It does not require any prior knowledge of database systems. It aims to explain what the “relational” qualifier means and why relational databases are an important milestone in database technology. Further reading: Relational databases are now a well-understood and mature technology and as such are covered in any good database text. An excellent and authoritative textbook is C. J. DATE, AnIntroduction to Database Systems, Addison-Wesley, now in its sixth edition (1995). Several examples in this talk come from the third edition (1981) of this book.

1

What is a database?
name......................... name......................... surname.................... name......................... surname.................... name......................... phone...........................
tracking img