This book sheds light on the principles behind the relational model, which is fundamental to all database-backed applications--and, consequently, most of the work that goes on in the computing world today. Database in Depth: The Relational Model for Practitioners goes beyond the hype and gets to the heart of how relational databases actually work.Ideal for experienced dataThis book sheds light on the principles behind the relational model, which is fundamental to all database-backed applications--and, consequently, most of the work that goes on in the computing world today. Database in Depth: The Relational Model for Practitioners goes beyond the hype and gets to the heart of how relational databases actually work.Ideal for experienced database developers and designers, this concise guide gives you a clear view of the technology--a view that's not influenced by any vendor or product. Featuring an extensive set of exercises, it will help you:understand why and how the relational model is still directly relevant to modern database technology (and will remain so for the foreseeable future)see why and how the SQL standard is seriously deficientuse the best current theoretical knowledge in the design of their databases and database applicationsmake informed decisions in their daily database professional activitiesDatabase in Depth will appeal not only to database developers and designers, but also to a diverse field of professionals and academics, including database administrators (DBAs), information modelers, database consultants, and more. Virtually everyone who deals with relational databases should have at least a passing understanding of the fundamentals of working with relational models.Author C.J. Date has been involved with the relational model from its earliest days. An exceptionally clear-thinking writer, Date lays out principle and theory in a manner that is easily understood. Few others can speak as authoritatively the topic of relational databases as Date can....
|Title||:||Database in Depth: Relational Theory for Practitioners|
|Number of Pages||:||232 Pages|
|Status||:||Available For Download|
|Last checked||:||21 Minutes ago!|
Database in Depth: Relational Theory for Practitioners Reviews
Awesome book, greatly recommended.Let me start with two disclaimers:* I'm writing the review after re-reading the book. My tone is probably less excited than it would have been if this was a first reading.* This book is "superseded" by another, called "SQL and Relational Theory". You should probably read that instead.Despite the name, this book is a gentle introduction to the relational theory. It explains the theoretical underpinnings of RDBMSs. If you don't know this stuff, the book is amazing. It uses a very understandable language and doesn't get too much into the math). It makes some very good points about how to use a relational databases (for example, why NULL values can be evil). There's even a chapter on normal forms that goes into satisfying detail.There are two downsides. First, the author is zealous at times. There is a lot of SQL-bashing that's not constructive – you get that it's not a great language the first time. Every rant rant after that gets annoying. Second, the practical application of the ideas in the book are a bit limited. It would be awesome if we can do everything C. J. Date talks about, but unfortunately existing RDBMS products don't allow it.Apart from that, it's a great book. It paints a picture of how relational databases should look like and leaves you sad that all the *SQL products look very differently.
»THE RELATIONAL MODEL HAS NEVER BEEN PROPERLY IMPLEMENTED IN COMMERCIAL FORM«* Autor C.J.Date gründete 1984 mit Relational-Model-Begründer E.F.Codd die Beratungsfirma "Codd and Date Consulting Group"* "Message of the book: Let's implement the relational model", "The relational model has never been properly implemented in commercial form", SQL only a first approximation* Autor C.J.Date kritisiert SQL (zu rigide, nutzt Bags statt Sets bzw. erlaubt und erzeugt Duplikate, zudem mit untersch. Grad bei untersch. Formulierungen fürs gleiche Query), kritisiert NULL bzw. dreiwertige Logik, erklärt und verwendet daher im Buch neben SQL seine eigene, der Theorie treuere Sprache Tutorial D* erste Buchhälfte führt durch die Begriffswelt des relationalen Modells; wer aus der SQL-only-Welt kommt, wird neben Tutorial D vielleicht auch noch neue (alte) Wörter lernen müssen; der Autor spricht irgendwann nicht mehr von Tabellen, Select etc. sondern theoriegemäß von Relation Variables (RelVars) und Relations (deren Werte), Projections usw.* C.J.Date schreibt gut, will verständlich sein, erwartet Menschen mit einem SQL-only-Hintergrund (das meint "for Practitioners", keine geheimen Praxistipps aus der Theorie), entwickelt manchen Strang "spiralförmig", nimmt also zuvor Behandeltes immer wieder auf und baut es aus (wirkt auf manche mglw. repetitiv); zweite Buchhälfte ist kurzatmiger und fordert mehr Niveau/Selberdenken beim Nachvollziehen der Zusammenhänge; insg. guter Stichwortgeber, musste hin und wieder fremdlesen (zB. Wikipedia); Zusammenfassung und Wiederholungs- bzw. Übungsfragen am Ende jedes Kapitels* interessantere Stränge im Buch: Database as a logical/formal system und rel. Algebra- DB not just data but facts (can be thought of as a collection of true propositions)- whole apparatus of formal logic becomes available for "the database problem"- when system evaluates some relational expression (when it responds to some query), it's deriving new truths from given ones; it's proving a theorem- "What A Database Really Is: Predicates and Propositions" by Hugh Darwin, 1998- relational algebra/relational calculus, closure, primitive and derived relational operators <-> expression transformation & transformation laws (autom. query rewrites/optimization)= Autor vermittelt grobe Idee von allem, aber nicht Fisch, nicht Fleisch, hat mehrere Bücher, mglw. mehr in "Logic and Databases"* Constraints-Kapitel berührt v.a. Datenbank-/Transition-/Type-Constraints; sind Business Rules, keine Praxishinweise (mglw. Off-Topic); bisschen theoret. Kritik an ggw. ACID-Transaktionen* DB design theory "still largely subjective in nature"- Autor behandelt nur wissenschaftlicheren Teil: formale Prinzipien, v.a. Normalisierung (inkl. 1-6 NF) und Orthogonalität= Reduktion von Redundanz bzw. deren Folgen: update-anomalies, jeopardized integrity, updates and queries harder to formulate (mistakes)- manches zu schnell behandelt, z.B. Zusammenhang Normalformen & Functional Dependencies, Join Dependencies, Mutlivalued Dependencies usw.- logical design: Constraints and predicates highly relevant here; Concentrate on what the data means, rather than on how it will be used; DB = faithul representation of the semantics of the situation, and constraints represent semantics; Process: (1.) pin down the RelVar predicates, (2.) map output from step 1 into RelVars and constraints (FDs, MVDs, JDs, ...)- C.J.Date kein Modeling-Fan: ER etc incapable of representing constraints- almost no "data independence" today: physical design change (performance) => logical design change (denormalization for performance) because phys. design maps 1:1 to logical design (relvar=file, tuple=record); new technology: TransRelational Model (TM) derives phys design autom.* Relational Model:- by Edgar Frank "Ted" Codd, 1969-paper, IBM- firmly founded in set theory & predicate logic- is rock solid and "right" and will endure because set theory & predicate logic are rock solid: elements of predicate logic go back over 2000 yrs (Aristotle)-- vs: object oriented model, hierarchical model, codasyl network model, semistructured model= arent in the same ballpark; dont deserve to be called models at all; OO = no consensus of what the model consists of- misleading to think in terms of "Structure + Integrity + Manipulation"- "Relations" as in mathematics (https://en.wikipedia.org/wiki/Finitary_relation)- "Types are sets of things we can talk about. Relations are (true) statements about those things. Types are to relations as nouns are to sentences. Without types we have nothing to talk about. Without relations, we can't say anything"- Relationen müssen nicht 2-dimensional sein (Tabellen)* Autor redet übrigens häufig von "Table Dee" und "Table Dum"; dass sie die Werte TRUE und FALSE als Relation for the sake of relational Algebra darstellen, ist mir erst beim Fremdlesen im Netz klar geworden; im Buch vielleicht irgendwo überlesen3.6 Stars
Fantastic description of the relational model.
A concise look at relational database theory. Some may find the author's style off-putting; he has very strong opinions about what he is discussing (I didn't). The author is unhappy with SQL because it deviates from the relational model in ways that can introduce uncertainty in some situations. He goes so far as to present his ideas in a language of his own, Tutorial D, because SQL is not up to his exacting standards.In this book relational databases are presented as mathematically sound, the releational mode derived from the same realm as set theory and predicate logic.This is not a how-to book. No real-world examples of optimization or the latest language features of an SQL dialect are presented. Instead it gives the reader a firm understanding of the timeless logical structures that should guide database design, data access, and DBMS implementation.An ultimately rewarding yet difficult book. Worth the time spent.The author's rigor and precision demand serious effort if one is to fully absorb his lesson. While reading it for the second time I has several moments of wanting to put the book down and give up. I bargained to myself, "Just get through it one more time, endure the puzzling theories of this man who is much cleverer than you—once more and you and your ignorance of the relational model will declare a truce". Sadly, the author has written another book based on this one, and meant to replace it. This I know becausesits on my desk and gloats, awaiting the moment I succumb to the charms of its cover and submit to another round of abuse.
This book made me a better SQL writer. While the author is often opinionated and strident, and windy, his rants are well-founded in a recognition of principle and theory going back to Aristotle, as he likes to point out. (Aristotle was not at his best on experimentation, but for logic, here we go).Two-valued logic, predicate logic, propositions, etc. -- any database professional should be concerned with these 'abstractions', but most aren't to their detriment, as Date aptly discusses.A writer of a highly-popular textbook on databases, Date goes the distance with providing a list of exercises at the end of each chapter, and he periodically asks the reader to think about the topic, and to check his claims. Not bad at all, I say, for a 'guru' of relational database theory.
Very poorly written book about databases. While the content was informative, reading the author's writing was an arduous task. He was repetitive, redundant, and said the same things over and over. He was way too colloquial in his writing, ya know what I mean, dawg? And the wordiness, my God! It's like, as one would say, in my opinion, reading, or thumbing through carelessly, a college freshman's essay. I could go on, and in chapter two of this review I do, about the lack of brevity, or shall I say the lack of interest, the folly or mistake of avoiding concise wording. I'm all like, wtf, bro?
The title says that the book is for practitioners, but still the subject is far from the physical database manager. Not that it is bad, but it is not that practical.I still learned some great things, and got a brush-up on key issues.
A must read book who love to play with databases. It'll clear up many concepts that were messy before.
A crisp and readable introduction to relational database theory for practitioners, and an entertaining polemic against the current crop of relational database systems and SQL.