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Question on NORMA Tutorial

Last post Wed, Dec 16 2009 13:55 by sbattisti. 2 replies.
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  • Mon, Dec 14 2009 16:28

    Question on NORMA Tutorial

    Hi folks,

    I'm a new forum member. I run a technical analysis group. We have a pretty junior group, more on the business side than the technical side. We're starting to explore ORM as a route to better definition of business "requirements".

    I've installed NORMA in my Visual Studio 2008 environment, and am just beginning to play around using the Powerpoint tutorial I found in the library (, and I'm running into questions.

    On the 4th slide of the presentation, a simple ORM schema is defined, with a Patient (.nr) a Patient Name, and a Drug (.name). Not being a programmer or an ORM expert by trade, I'm a little confused by the .nr and .name references. Where do these extensions come from, and what do they mean?

    Or, where should I go for more detailed documentation? Sorry for what is undoubtedly a very basic question!

    Thanks very much folks!


  • Mon, Dec 14 2009 18:59 In reply to

    • Ken Evans
    • Top 10 Contributor
    • Joined on Sun, Nov 18 2007
    • Stickford, UK
    • Posts 785

    Re: Question on NORMA Tutorial

    Hi Steve,
    Welcome to the ORM foundation website.

    The (.nr) reference refers to the use of a number to uniquely identify a Patient.
    Similarly the (.name) reference is used to uniquely identify a Drug.
    Another example is (.vin) which is a unique "Vehicle Identification Number") - See >

    One of the big problems in defining requirements (for anything) is that natural language is widely used but it is not suited to this task because natural language is ambiguous and vague.

    So, in ORM we uniquely identify things by using references such as (.nr) (.id) and so on.
    Unique identification of "things" is one of the core logical principles on which ORM is based. (Google "existential quantifier" for more)

    "More detailed documentation" is available in the book "Information Modeling and Relational Databases - Second edition . (see the link on the home page)

    However, to make effective use of ORM, there is a great deal to understand. That's why Terry's book is almost 1000 pages. From time to time I run ORM courses that are tailored to meet the specific needs of each client. 

    Hope this helps


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  • Wed, Dec 16 2009 13:55 In reply to

    Re: Question on NORMA Tutorial

    Excellent, thanks very much for the information! We have a copy of Terry's book lying around here somewhere. I'll do some studying. ;)


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