Re: Date, the relational model and the application (software layer)

On Thu, 11 Mar 2004 22:49:42 +0000, mountain man wrote:

> My reading of Date's work in regard to his reference to the application
> software layer is that is is located external to the (R)DBMS as seems
> indicated by a number of diagrams in the introductory chapters.

        I suspect this is one of the instances where Date doesn't say much because it would take much more time and result in an encyclopædia, and would be too much to try to sell -- the RM by itself is already a hard enough sale.

        Now I do know that Alphora Dataphor, the virtual RDBMS that AFAIK is the only current full-featured RM implementation -- although there are two free software libraries --, does stores all the application in a RDB, and does push things like data entry consistency to the front-end transparently.

        Obviously this is just a convenience, and not a formal requirement AFAIU. One could just have a fast enough system and validate every field entered in the backend, but it just makes sense to have the frontend know about data integrity enforcement automatically.

        On a related note, Nathan Allan Alphora's founder and Dataphor's architect believes, and I agree, that all data should be relationally represented in a computer system, and thus eventually we'd have a relational OS.

        I even architected a pie-in-the-sky scheme for migration, calling for a valid D true RDBMS being implemented as a GNU/Hurd personality, perhaps in conjunction with the Lisp system personality originally envisioned by RMS; as people would have the systems programming flexibility and power of the RM, functional systems programming, and the multi-server microkernel architecture, *perhaps* the advantages would be enough that new apps would be written to this reformed platform, and POSIX would be just legacy, as powerful as it may be. Obviously this is just my daydreaming, nothing at all related to neither Alphora nor Date.

        Caveat lector: Date is on Alphora's (¿informal?) advisory board, but this does not necessarily mean he does wholeheartedly agree with what's on Dataphor, much less that he has given extented thought to any issue brought up by or implemented in it.

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