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1. Database Truth

"The RDM is a formal system. It has two parts. Semantics its outside the formal language (which is Deductive Subsystem), but not outside the interpretation (i.e., application) of that language (Interpretation Subsystem). Without an Interpretation Subsystem there is no possibility of applying the formal system and it remains an abstract game of symbols."

"Codd's 1979 paper described a way to "capture" semantics using the relational formalism. That formalism doesn't tell you how to discover semantics, but if you have them, then he showed (at least to some degree) how to express those semantics relationally."

"Semantics is about applying the RDM to some subject. In effect, what you do is restrict the power of the abstract formalism so that it is more closely aligned with your intended use. In my terminology, that means you:

• Create axioms (expressed as constraints), limiting the vocabulary to the subject matter (and making it finite and usually fairly small); and,
• Restrict the possible interpretations that can be used consistently with the resulting subset of the formalism."

                                                          --David McGoveran

2. Do You Know What's Wrong With This Picture?

"When someone refers to a relation in a database course, what does that mean?"

"It means that it is time to go to Wikipedia."

"A relation in the context of modeling a problem will include the fields and possibly the identification of fields which have relationships with other relations."

"A relation is a data structure which consists of a heading and an unordered set of tuples which share the same type."

"I was trying to show that, in SQL, a relation is more than just a table. Queries return relations. And within a query, relational math is happening, with many intermediate results, that themselves are relations."

"A relation is an abstract structure which contains a set of attributes, and a relvar is the dataset status in a particular moment of this relation. The first one can be considered as the table definition with columns, and the second one is dataset in this table." 

"Tuples need not have a key (or any way of locating them?) Having tried to answer this question so that I could explain it to my students, I am forced to the conclusion that the theory has nothing whatsoever to do with "data" in the usual sense. Perhaps information Theory would have been a better basis for data systems, rather than Mathematics? Computer applications are notably different from Physics, which math was created to model, and its child, Engineering. I think data was never intended to be "true", it must be useful."

                  --What is a relation in database terminology?, StackOverflow.com

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3. To Laugh or Cry?

Schema Design - Attributes Arrangement

4. Publications

• NEW: The Key to Relational Keys: A New Perspective. 
• THE DBDEBUNK GUIDE TO MISCONCEPTIONS ABOUT DATA FUNDAMENTALS, my latest book, is available to order here.

• Logical Symmetric Access, Data Sublanguage, Kinds of Relations, Database Redundancy and Consistency, paper #2 in the new UNDERSTANDING OF THE REAL RDM series, is available for ordering here. 
• Interpretation and Representation of Database Relations, paper #1 in the new UNDERSTANDING OF THE REAL RDM series, is available for ordering here.

5. Housekeeping

Following the discontinuation of AllAnalytics the references and links to my columns there no longer work. I have replaced them with the actual content for 2017 and will add earlier years later. The links within the content to AllAnalytics posts no longer work either, but those to other sources do.
 

6. Oldie But Goodie

Monash Balderdash

7. The Industry

• A Brief History of Databases
• Main-Memory Database Overview with Slides
• Learning to program is getting harder
• Complexity Bias: Why We Prefer Complicated to Simple 
• Covering Your Tracks in the Age of Technology 
• How Facebook and Google build a picture of who you really are 
• We Are Running Out of Time to Make Algorithms Fair 
• We think we know more than we do—including how machines will behave

And Now for Something Completely Different: The PostWest

Not much difference between the Party State and the Corporate State: both evil and socially destructive.

• MUST READ: A personal inquiry into the tech industry 
• It's not the the shooters: The Empty Rituals of an American Massacre, The U.S. Fights Terrorism—But Not School Shootings, 'Show Us the Carnage'; it's the sick society that produces in mass people devoid of the concept of love: Why Silicon Valley singles are giving up on the algorithms of love
• How a handful of tech companies control billions of minds every day
• How Trump's budget would cut the safety net for the poorest Americans
• Looting the treasury and corruption clear indicators of national decadence and empire collapse: Germany’s Coffers Are Overflowing, But No One Is Talking About Tax Cuts, A Taste of Washington Corruption
• Aetna Medical Director Admits He Never Reviewed Medical Records Before Denying Care
• When Welfare Decisions Are Left to Algorithms
• The Free Market Threat to Democracy
• Opioid makers paid millions to advocacy groups
• Monopoly Now Wants You to Cheat—Just Like Real Capitalists
• Wells Fargo Screws Customers Yet Again
• Electronics-recycling innovator faces prison for trying to extend computers' lives
• Court reinstates SF ban on evicting teachers for profit during school year
• The entirely unnecessary demise of Barnes & Noble
• Can Your Hip Replacement Kill You

Palestinian "Support" Nothing More than Another Form of Anti-semitism

• Understanding Saeb Erekat's claim that Trump is wrecking the Palestinian peace process
• How Israel Should Handle Gaza’s “Humanitarian Disaster”
• Florida shooter hates Jews, claims they want to destroy world
• Anti-Semitic hate speech incidents in Austria at all-time high
• Poland proves what it tried to deny: PM is the worst kind of Anti-semite, Polish Jews stunned, scared by eruption of anti-Semitism,

Note: I will not publish or respond to anonymous comments. If you have something to say, stand behind it. Otherwise don't bother, it'll be ignored.