Data and database fundamentals made accessible to and misconceptions dispelled for the thinking data professional and user.
Normal 0 Note: In MEANING AND THE DATA MODEL I mentioned a recent LinkedIn exchange that prompted that post. It also reminded me of an older post, which had triggered two exchanges: one @DBDebunk, and another @ https://news.ycombinator.com/item?id=12437389&goto=news in which I participated at the time. I decided to update the older post and I strongly recommend the YCombinator exchange,…
Normal 0 Table of Contents Introduction 1. Entities, Properties, Names, and Identifiability 2. Relational Representation 3. Kinds of Keys 3.1. Candidate, Primary, and Alternate Keys 3.2. Natural and Surrogate Keys 4. Primary Formal Mandate 5. Primary Key Designation 6. Primary Keys and Performance 6.1. Indexes Conclusion Appendix: Primary Keys, Duplicates and SQL
Recently I participated in a LinkedIn exchange initiated by the following statement: “First-Order Predicate Logic is quietly breaking enterprise semantics. FOPL assumes meaning can be expressed as predicates applied to entities: subject → predicate → object That works beautifully in theory. It fails in practice. Because the predicate is where ambiguity hides. So you can build vast semantic graphs…
Normal 0 Table of Contents Introduction 1 Data Types 1.1 Abstract Data Types 2 Database Domains 2.1 Domain Adaptations 2.1.1 Attributes 2.1.2 Tuple States 2.2 Domain Definition 2.2.1 Type Specification 2.2.2 Domain Operators 3 Kinds of Domains 3.1 Base Domains 3.2 Primitive Domains 3.3 Atomic ("Simple") Domains 3.4 Derived ("Complex") Domains 4 DBMS Domain Support Appendix 1: Complex Domain…
As we explain in Logical Database Design (forthcoming), LDD assigns the meaning of terms in conceptual models (CMs)—properties, entities, groups, multigroup—to non-logical symbols of a formal logic theory. If the theory is RDM, the symbols stand for sets—domains/attributes, tuples, relations, database—adapted for database management. For each CM the theory acquires an interpretation, which…
This was said years ago: ” Table (n.) – a collection of information (data?) describing a population of entities which possess some common characteristics, called attributes. -itis – “suffix denoting diseases characterized by inflammation, itself often caused by an infection.” ---------- from the Wikipedia Wiktionary.” Tables are the building block of relational databases. Tables must generally be…
Normal 0 “... In ORM there is no concept of an entity record (tuple), although relational tables can be automatically generated from an ORM model (furthermore, guaranteed to be fully normalized).” --Online comment “ Object Role Modeling (ORM) is a ...a fact-oriented modeling approach for specifying, transforming, and querying information at a conceptual level. Unlike [other modeling approaches]…
Normal 0 Chris Date once published an article at the old DBDebunk titled “Models, Models, Everywhere, Nor Any Time to Think” . If you want to get a hold of what he meant then, you oughta do a search on the title now and see what you get. The continuous proliferation of models is an indication and measure of the disregard, if not outright hostility of the industry to sound theoretical foundations.…
Normal 0 Normal 0 “ If we step back and look at what RDBMS is, we’ll no doubt be able to conclude that, as its name suggests (i.e., Relational Database Management System), it is a system that specializes in managing the data in a relational fashion. Nothing more. Folks, it’s important to keep in mind that it manages the data, not the MEANING of the data! And if you really need a parallel, RDBMS is…
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Table of Contents Introduction 1. Logical Symmetric Access 2. Universal Data Sublanguage 2.1. FOPL vs. SOL 2.2. Relational Completeness 2.3. Computational Completeness and Hosting 3. Kinds of Relations 3.1. Expressible and Named Relations 3.2. Derived Relations 3.3. Data Storage 4. Derived Relations and Redundancy 4.1. Database Consistency 5. Database Catalog Conclusion
Table of Contents Series Preface Introduction 1. Interpretation of Database Relations 1.1. Attributes as Constrained Domains 1.2. Time-Varying Relations 2. Representation of Database Relations 2.1. Physical Data Independence 2.1.1. Uniquely Named Attributes 2.1.2. Primary Keys 2.1.3. Relations and R-tables 3. Normalization 3.1. First Normal Form and “Simple” Domains 3.2. Normalization and…
In "Codd Almighty! Has it been half a century of SQL already?" the Register's Lindsay Clark interviews "Donald Chamberlin, Michael Stonebraker and more" about the legendary programming [sic] language. Chamberlin with Raymond Boyce were the authors of "the 1974 paper SEQUEL: A structured English query language as a way of addressing data in IBM's newly proposed System R, the first database to…
I am working on entirely new papers (not re-writes) in the PRACTICAL DATABASE FOUNDATIONS series. I have already published two: THE FIRST NORMAL FORM - A DEFINITIVE GUIDE PRIMARY KEYS - A NEW UNDERSTANDING available for ordering from the PAPERS page, and two more: RELATIONAL DATABASE DOMAINS: A DEFINITIVE GUIDE DATABASE RELATIONS: A DEFINITIVE GUIDE are in progress and forthcoming, respectively.…
I am working on entirely new papers (not re-writes) in the PRACTICAL DATABASE FOUNDATIONS series. I have already published two: THE FIRST NORMAL FORM - A DEFINITIVE GUIDE PRIMARY KEYS - A NEW UNDERSTANDING available for ordering from the PAPERS , and two more: RELATIONAL DATABASE DOMAINS: A DEFINITIVE GUIDE DATABASE RELATIONS: A DEFINITIVE GUIDE are in progress and forthcoming, respectively. In…
FT Data Sublanguage & Programming Languages FT Relational Domains & Programming Data Yypes TLC RDM & "Arbitrary Data Types" FT RDM & Complex Domains FT RDM & Objects Permanent Identification SMS Surrogate Keys FT Primitive & Derived Domains SMS Primary Keys: Mandate & Selection FT Database Relations & Functions
I am working on entirely new papers (not re-writes) in the PRACTICAL DATABASE FOUNDATIONS series. I have already published two: THE FIRST NORMAL FORM - A DEFINITIVE GUIDE PRIMARY KEYS - A NEW UNDERSTANDING available for ordering from the PAPERS page, and two more: RELATIONAL DATABASE DOMAINS: A DEFINITIVE GUIDE DATABASE RELATIONS: A DEFINITIVE GUIDE are in progress and forthcoming, respectively.…
FT Relation Interpretation L/C Tree Prediction in SQL L/C " Purpose built systems" SMS Primary Key Immutability FT Kinds of Surrogate Key SMS Imaginary Keys FT Uniqueness Is Relationship SMS SST/FOPL & Keys
I am working on entirely new papers (not re-writes) in the PRACTICAL DATABASE FOUNDATIONS series. I have already published two: THE FIRST NORMAL FORM - A DEFINITIVE GUIDE PRIMARY KEYS - A NEW UNDERSTANDING available for ordering from the PAPERS page, and two more: RELATIONAL DATABASE DOMAINS: A DEFINITIVE GUIDE DATABASE RELATIONS: A DEFINITIVE GUIDE are in progress and forthcoming, respectively.…
In Part 1 we introduced in the conceptual model (CM) the metalogical designation property . It represents—in the absence of known shared defining properties of an entity type, the designation by a group 's definer that an entity identifier (aka assigned name) or property value is a member of the group. Such a group is not a group of entities, but a group of name and property values. In the logical…
with David McGovern One purpose of our contributions here is to suggest a vocabulary that avoids confusion not just within the formal logical level, but also between conceptual and logical terminologies, which is widespread in the industry and is exacerbated by limitations of natural language (NL). We use the following terminology in our approach to conceptual modeling: Objects are: - Primitive…
Due to: 1. Taking care of some health issues that have accumulated (not getting any younger); 2. Concentration on the Israel-Hamas War; 3. Effort to update old papers and write new ones; 4. Much needed rest and the holidays. I am taking the remaining of the year off and will re-start my contributions in January. Wishing you and yours season's greetings and happy holidays!