Friday, September 22, 2017

This Week

1. Database Truth of the Week

“If the data sub-language ... has the power of second order predicate logic (SOPL), expressions are possible that cannot be evaluated (for example, self-referencing expressions) and the formal language is then undecidable, an algorithm to implement a declarative query language is impossible and all hope of physical independence is lost." --David McGoveran


2. What's Wrong With This Database Picture?

"Our terminology is broken beyond repair. [Let me] point out some problems with Date's use of terminology, specifically in two cases.
"type" = "domain": I fully understand why one might equate "type" and "domain", but ... in today's programming practice, "type" and "domain" are quite different. The word "type" is largely tied to system-level (or "physical"-level) definitions of data, while a "domain" is thought of as an abstract set of acceptable values.

"class" != "relvar": In simple terms, the word "class" applies to a collection of values allowed by a predicate, regardless of whether such a collection could actually exist. Every set has a corresponding class, although a class may have no corresponding set ... in mathematical logic, a "relation" is a "class" (and trivially also a "set"), which contributes to confusion.
In modern programming parlance "class" is generally distinguished from "type" only in that "type" refers to "primitive" (system-defined) data definitions while "class" refers to higher-level (user-defined) data definitions. This distinction is almost arbitrary, and in some contexts, "type" and "class" are actually synonymous."


3. To Laugh or Cry?

"From the get go, relational databases have been one of the biggest challenges in the usage of Agile software practices. They’re laborious to use in automated testing, often expensive in time or money to install or deploy, the change management is a bit harder because you can’t just replace the existing database objects the way we can with other code, and I absolutely think it’s reduces reversibility in your system architecture compared to other options. That being said, there are some practices and processes I think you should adopt so that your Agile development process doesn’t crash and burn when a relational database is involved." --Jeremy Miller, Thoughts on Agile Database Development


4. Publications


Reviews



5. Oldies but Goodies



6. Elsewhere



7. Interesting




8. The Sillicon Valley State: Technology as Mechanism of Tyranny and the Inhuman Destruction of Free Civilized Society



And Now for Something Completely Different -- The PostWest: Indicators of Western Civilization Collapse

"Looking back this week on Sept. 11, it’s hard not to conclude that Osama bin Laden won a significant victory. With relatively little money and a small band of suicidal fanatics, he reconfigured the policy of a superpower in a region of vital interest for 16 years, at a high cost in American treasure and lives and global influence that may never be recaptured. From the Iraq war to Afghanistan, and from the Iran nuclear deal to the anti-ISIS campaign, our foreign policy is a bipartisan train wreck endangering passengers and bystanders alike. Bin Laden didn’t destroy America like he set out to do, he did something much worse: He set America on a path to self-destruction. The way I see it, Sept. 11 is how we got Donald Trump. --Lee Smith, Democratic and Republican Elites Are Using Trump to Whitewash 16 Years of Foreign-Policy Disasters
"We deserve Trump, though. God, do we deserve him. We Americans have some good qualities, too, don't get me wrong. But we're also a bloodthirsty Mr. Hyde nation that subsists on massacres and slave labor and leaves victims half-alive and crawling over deserts and jungles, while we sit stuffing ourselves on couches and blathering about our "American exceptionalism." ... This is who we've always been, a nation of madmen and sociopaths, for whom murder is a line item, kept hidden via a long list of semantic self-deceptions, from "manifest destiny" to "collateral damage." We're used to presidents being the soul of probity, kind Dads and struggling Atlases, humbled by the terrible responsibility, proof to ourselves of our goodness. Now, the mask of respectability is gone, and we feel sorry for ourselves, because the sickness is showing." --Matt Taibbi, The Madness of Donald Trump
"Coalitions of health professionals that have spoken publicly against the measure so far include the American Medical Association (“Provisions violate longstanding AMA policy”), the American Psychiatric Association (“This bill harms our most vulnerable patients”), the American Public Health Association (“Graham-Cassidy would devastate the Medicaid program, increase out-of-pocket costs, and weaken or eliminate protections for people living with preexisting conditions”), the National Institute for Reproductive Health (“the Graham-Cassidy bill preys on underserved communities ... a clear and present danger”), and Federation of American Hospitals (“It could disrupt access to health care for millions of the more than 70 million Americans”). This is in addition to the American Academy of Pediatrics, Association of American Medical Colleges, American College of Obstetricians and Gynecologists, and many others." --Doctors: Do No Harm
"If the first figure is his fee, as it reportedly is for the Cantor Fitzgerald speech as well, he’ll pocket $1.2 million from three Wall Street speeches in about a month’s time. The issue is not just the cashing in on career-long, eager service to mega-wealthy Wall Street bankers — including especially his failure to prosecute not one of them for massive and systemic fraud, let’s remember. That’s the smallest of the problems with this story. A larger issue is its effect on the desperate attempt of the Democratic Party to distance its current self-presentation, “The Party That Speaks For The People,” from its most recent self, “The Party Of The Top Ten Percent.” Or at least, its attempt to appear to create that distance." --Gaius Publius, Obama Follows Clinton, Boards the Millionaire Speech Train to Wall Street


Insanities of the Week


More Self-destruction


Book of the Week (Order via this link to support this site)


Video of the Week

State of Surveillance

Pinch Me of the Week


Upside Down and Backwards this Week


Anti-Semitism, Hypocrisy, the Myth of a "Palestinian Nation" and the "Peace Process" Delusion


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


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2 comments:

  1. The comments on the first "case" are outright weird. The author seems to use a state of affairs as it stands in "current programming practice" to demonstrate/claim problems of clarity in Date's writings. Date writes exactly because "current programming practice" is so confused and so conflated and so broken and so crippled. Date writes in an attempt to show the way OUT OF that confusion and conflation and brokenness and cripple. So exactly in which way connecting certain ideas of Date's with a description of the current state of affairs in programming practice by putting "but ..." in between them, could lead to some meaningful and relevant insight, is beyond me.

    The class=relvar thing has always been beyond me as well (and that holds even more for all the commentary it has engendered). Right up to the point that I once pondered that the *real* blunder might be to think that anyone is actually committing the class=relvar blunder. I mean, what does it even *mean* to "equate" one component of some given programming paradigm, with some other component of some radically different programming paradigm ? imo, no useful conclusions/insights can come out of any attempt to do any such "equating". Or of trying to discuss the point. As this particular example seems to show.

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    Replies
    1. This is a large source of the confusion, but not all. Class and type as used in the RDM are well defined formal concepts from set theory, but are not known as such and understood by practitioners (possibly even CJD and HD) independent of the confusion with programming.

      Ditto with respect to relvars. Set theory has no concept of variables to which values can be
      destructively assigned -- no assignment. That is why Codd skirted the issue by using "time-varying relations" and did not include EXPLICIT
      variable semantics in relational data sub-languages. That must be handled "under the cover" and should not be exposed to users. Details in David's
      forthcoming book.

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