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Relational Remodelled

A 2 Day Seminar

Speaker:

Chris Date

"I am grateful that Chris is clear on the subjects, and explains them such that they seem fairly simple. This class is one of the high points in my professional life."

"Yes I do think the relational model is deeper after this class. I really enjoyed this class and the instructor presented the material beautifully"

"The course was excellent. It offered an opportunity to hear from a world authority on the relational model. The lecture content, handouts, and presentation style were of the highest quality"

This seminar offers an unrivalled opportunity to hear about some of the most recent developments at the foundations of database technology, from one of the world's foremost advocates and expounders of relational database theory and practice. Much of the material presented is NEW and is not currently available in any other live forum.

It is trite but true to say that the relational model is the foundation of the entire database field. Yet almost no one understands it! We wouldn't think much of an electronics engineer who didn't know Ohm's Law or a chemist who didn't know the periodic table - yet the IT industry seems all too willing to tolerate "database professionals" who are almost completely ignorant of the foundations of their own field (and even brag about their ignorance, in certain cases). No wonder, then, that such spectacular mistakes occur in the design and/or implementation of databases, and database applications, and database products, and database standards (and so on - this is not an exhaustive list).

Part of the problem lies, perhaps, in the all too common misconception that if something is theoretical, it can't be practical (despite the fact that database management is a multi-billion-dollar industry totally founded on one great theoretical idea). Another part of the problem is, perhaps, the fact that most relational presentations - even those by dedicated relational advocates - quite deliberately focus on the model's intuitive simplicity and ignore aspects and implications that might seem esoteric or advanced. Such an emphasis unfortunately does the cause of genuine understanding a grave disservice. The fact is that the relational model is much deeper, more robust, and more important than most people realize.

This seminar examines the relational model in depth. It consists of a series of "closer looks" at various familiar features (e.g., integrity, domains, views, primary keys), together with careful explanations of some less familiar aspects (e.g., nullology, essentiality, expression transformation, "the theory of database relativity"). Overall, the intent is to present a remodeled version of relational theory - one that will help true database professionals understand the relational model in depth and make use of that understanding in their day-to-day database activities.

DBMS designers, implementers, and other vendor personnel
Database consultants
Data and database administrators
Information modelers and database designers
Database application designers and implementers
Computer science professors specializing in database matters
Database students, both graduate and undergraduate
People responsible for DBMS product evaluation and acquisition

This highly intensive seminar is not meant for beginners: Attendees will be expected to have a basic knowledge of the relational model (though this material will be briefly reviewed at the outset). They should also be able to understand simple SQL coding examples.

On completion of this seminar, attendees will:

Understand why and how the relational model is still directly relevant to modern database technology (and will remain so for as far as anyone can see)
See why and how the SQL standard is seriously deficient
Be able to use the best current theoretical knowledge in the design of their databases and database applications
Be able to make informed decisions in their daily database professional activities
Have at least an overview perspective on The Third Manifesto and see how it holds hope for the future

1. Preliminaries

Significance and objectives
The original model: a review
Relations vs. relvars
Values vs. variables
Model vs. implementation

2. Essentiality

Data structures
Relational vs. nonrelational databases
Ordering
The Information Principle

3. Domains

Domains and data types
"Domain check override"
Data value atomicity
Defining domains

4. Relational algebra I: Basics

Importance of closure
Importance of attribute naming
Expression transformation
Optimization
The heresy of duplicates

5. Relational algebra II: Extensions

EXTEND and SUMMARIZE
Relational comparisons
Should divide be dropped?
Recursive queries
Quota queries

6. Relational integrity I: Keys

Candidate keys
Primary and alternate keys
The primacy of primary keys (?)

7. Relational integrity II: Constraints and predicates

Constraints are predicates
When are constraints checked?
Internal vs. external predicates
Correctness vs. consistency
A constraint classification scheme
A formal perspective

8. Relations

Relations are n-dimensional
Kinds of relations
The theory of database relativity

9. The relational model is set-level

Retrieval operations
Update operations
Tuple-level operations (?)
Some implications

10. Nullology

Empty types
Empty relations
Empty headings
Empty operand lists
Empty partitions of headings
Empty determinants and keys

11. Missing information

Various kinds of null
UNK, unk, and three-valued logic (3VL)
Consequences of the 3VL approach
SQL's implementation of 3VL
Outer join
Further thoughts
The "special values" scheme

12. Relation-valued attributes (RVAs)

RVAs are legal!
RVAs and outer join
RVAs and relational comparisons
RVAs and database design

13. Database design I: Some remarks on normalization

The "difficult" normal forms
A new definition of BCNF
Normalization is not a panacea ...
... but don't denormalize!
New normalization theorems

14. Database design II: More science!

Examples of bad design
Overlapping meanings
The Principle of Orthogonal Design
Some implications

15. Views

View updating: general remarks
Some fundamental principles
Union, intersection, and difference views
Other views: a little heresy!

16. What IS the relational model?

Summary
Precise definition
Five components
Relational remodeled

Appendix: The Third Manifesto

Background
RM prescriptions and proscriptions
OO prescriptions and proscriptions
RM and OO suggestions
Future directions

Attendees will receive a workbook containing copies of the speaker's slides, together with a selection of technical papers and other background reading material.

Recent Developments in Database Technology: Type Inheritance and Temporal Data
Speaker: Chris Date
Dates: 19-21 March 2003 Location: London
Register for both Chris Date events taking place during the week of 17 March 2003 and save £250

Chris Date

Chris Date
C. J. Date is an independent author, lecturer, researcher, and consultant, specializing in relational database technology. He is best known for his book An Introduction to Database Systems (seventh edition published in 2000), which has sold well over 650,000 copies and is used by several hundred colleges and universities worldwide. He is also the author of many other books on database management, including most recently Foundation for Future Database Systems: The Third Manifesto (2nd edition, coauthored with Hugh Darwen); The Database Relational Model: A Retrospective Review and Analysis; WHAT Not HOW: The Business Rules Approach to Application Development (all published by Addison-Wesley in 2000); and Temporal Data and the Relational Model (coauthored with Hugh Darwen and Nikos A. Lorentzos, published by Morgan Kaufmann in 2003). Mr. Date enjoys a reputation that is second to none for his ability to communicate complex technical subjects in a clear and understandable fashion.