UPDATE 1: I have added Jim Starkey's reply to David's initial response (with my brief comments) and David's reply to it below.
UPDATE 2: I have made a few minor corrections and fixed end-note formatting problems.
© 2014 David McGoveran – All Rights Reserved
Jim Starkey's Response (n above LinkedIn exchange):
David McGoveran's article is well worth reading, a welcome break from the insulting, content-free snears from the RDM camp.
David challenges me to name one aspect of human knowledge that can't be represented in rows and columns. Fair enough. David, your article itself is an excellent example of something that can't be represented--and found--with a row and column representation. True (he said patting himself on the back), it can be represented as a BLOB and on some systems even an HTML structured blob. But it can't be searched with first order predicate logic.
Personally, I'm a fan of first order predicate logic. Who isn't? It's the fundamental language of mathematics. I'm sure it wasn't lost of David that the Datatrieve language was, indeed, first order predicate logic extended with sufficient (and optional) syntactic sugar to be English-like. I was very pleased with the degree that the language was accepted by people ranging from mathematicians and researchers to secretaries (who, more than often, found they had, in fact, found new careers as programmers).
The problem with first order predicate logical is that each predicate in a full expression must resolve to either true or false (let's ignore nulls). Word search can't be expressed in first order predicate logical. If you search for the phrase "first order predicate logical", you're going a rather fuzzy search for documents that contain words in that phrase. And, unlike first order predicate logic, the application of the search phrase to a specific document isn't true or false but a "hit score" where a document containing those words in order without intervening words will be scored the highest (and ranked among other such has by the relative position of the phrase in the document). At the bottom are documents that containing at most one of the words. It's logic, David, it just isn't first order predicate logic.
David says, "Nothing in RDM limits the simplicity or complexity of those semantics." I respectively disagree. Restricting a data model to first order predicate logic denies the fact that the most successful computing company in mankind's history, Google, is based on search, not first order predicate logic.
How is this possible? The answer, I'm afraid, is that the database community, especially the academic database community, suffers from a profound case of Head in Sand Syndrome (HISS), which can be paraphrased, "if it wasn't in my CS 101 class, it doesn't exist."
David, you write well and are clearly a decent and thoughtful fellow. Pull your head out of the sand. First order predicate logic is not the be all and end all of human thinking. And, not incidentally, first order predicate logic is not restrict to sets. [Of course Amorphous uses first order predicate logic, Duh. It also implements weighted hit search semantics and user control over the fuzziness in between.]
Fabian Pascal Comments:
- Since RDM is FPL applied to database management, how are Jim's comments about FPL consistent with his claim that RDM "is spent"? (see David's comment above)
- Hard to believe Jim's comments about FPL and search, but I'll let David address this much better.
- I don't know whether to laugh or cry: Does Google manage its corporate data with searches?
- This is an excellent example of the disregard by the industry of data fundamentals and its consequences. The problem with academia is the opposite of what Jim complains about: instead of leading industry with fundamental research and education, academics jump on every industry fad bandwagon that lacks sound foundation. Vendor training and tool certification are substituted for education, Jim's arguments being the result.
- formulates this model formally and
- demonstrates that it has a theoretical foundation
- as sound and complete as the RM
- does everything that the relational model does and
- either more, or is more general or simpler
David McGoveran Second Response
© 2014 David McGoveran – All Rights Reserved
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