Welcome!
What is ORM? ORM is an acronym for "Object-Role Modeling" and is a way to build information models from which logical models can be automatically derived. ORM uses the principles of "fact oriented modeling" which has only one data structure (the fact type) but has many constraint types and an easy to understand graphical notation. Many people believe that ORM provides a simpler and more powerful approach to information modeling than other approaches such as Entity-Relationship modeling and UML.
What is the history of ORM? The roots of ORM can be traced to research into semantic modeling for information systems in Europe during the 1970's. There were many pioneers and this short summary does not by any means mention them all. An early contribution came in 1973 when M Senko wrote about "data structuring" in the IBM Systems Journal. In 1974 JR Abrial contributed an article about "Data Semantics". In June 1975, Eckhard Falkenberg's doctoral thesis was published and in 1976 one of Falkenberg's papers mentions the term "object-role model". In the same year, Sjir Nijssen wrote about "a gross architecture for the next generation database management systems". In 1989 Terry Halpin completed his PhD thesis on ORM and in the same year he co-authored a book with Sjir Nijssen "Conceptual Schema and Relational Database Design".
How can I learn more? The authoritatve book on ORM is Terry Halpin's 2008 "Big Brown Book" entitled "Information Modeling and Relational Databases - Second Edition". (The first edition was published in 2001). You can order the Big Brown Book by clicking on the "Second Edition" image (see sidebar - Books). You may also read the Library documents and participate in the Forum.
Are there any ORM Tools? The growth of ORM has followed the availability of a series of steadily improving ORM tools. The early ORM tools such as IAST (Control Data) and RIDL* were followed by InfoDesigner, InfoModeler and VisioModeler. When Microsoft bought the Visio Corporation, Microsoft extended the VisioModeler ORM functionality and made it a component of Microsoft Visual Studio called "Microsoft Visio for Enterprise Architects" .
Microsoft's first ORM implementation appeared in the 2003 Enterprise Architects release of Visual Studio as a component called "Microsoft Visio for Enterprise Architects". In the same year, a companion "how to" book was published by Morgan Kaufmann entitled "Database Modeling with Microsoft Visio for Enterprise Architects". (see sidebar) Microsoft has retained the ORM functionality in the high-end version of Visual Studio 2005 and the Morgan Kaufmann book remains a suitable user guide for both versions.
The next "in the works" Visual Studio ORM tool is called NORMA (Neumont ORM Architect for Visual Studio). You can download NORMA from the Library.
Forum The Forum is for discussing ORM related topics. Most of the discussions can be viewed by guests but to participate you have to register on the site. Some discussions are not visible to all registered members because they are for specialised sub-groups only. However, if you don't see a topic that you feel should be given its own Forum, please post a message in the "Request a Topic" Forum. Your post should include a title, a description of the scope, how it relates to ORM and why the ORM community will find it of interest.
Library The Library contains ORM related documents from many sources. Most documents are in PDF format but there may also be multimedia file types and software that you can download.
Surveys The survey system is now active and surveys will be posted from time to time.
Visitors may browse the Library and Forum. Registered members can download documents and participate in the forum discussions. Registration is free - just click on the "Join" button at the top right of the screen and follow the instructions.
Regards
Ken Evans
What's New
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I navigated to a page (tab) in my model. No icon was selected. I typed notes into the ORM Notes Editor. Thought I had expressed a good statement about the entire page. Navigated away from this and returned to check my notes. GONE! Or at least not visible. Is this a bug or a 'feature'?
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The majority of these result from explicitly setting a preferred identifier, which orphans the old FactType/ValueType pair. I also change the default in the Tools/Options/ORM Designer page so Delete deletes the underlying object and Ctrl-Delete deletes the shape (see the Delete Key Behavior option). The easiest way to see these is to scan the ObjectTypes...
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Yes, they're standard VS designer commands available on the main VS menu. You'll see a Format menu appear when you have alignable combinations of top-level shapes selected. We don't currently support aligning to role boxes (the DSL designer has shapes, subshapes, and shapesubfields. Each role box is a shapesubfield), but it's on the...
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I have a few objects that were deleted from diagrams but not from the data. I call these 'orphans'. How can I find orphaned objects?
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As you know, the Oslo details at this point are still very sketchy. Certainly, the idea of a model repository is we've discussed internally, but is also something we want to be very careful with. If Oslo can facilitate our requirements, we would obviously be thrilled to have a platform to build on if it fulfills our requirements. A few random thoughts...