User experience

orm notations misunderstanding

rolemo — Sun, 12 Oct 2008 20:58:26 GMT

hi,

well its my first visit here, i must say that the forum seems knid of a lonely place...

anyway, what i wa nted to ask about re the uniqness arrows. you know, the small ones just abouve the facts box. thing is i cant understand why not to use the UML [0...1], [1...*] etc. theseare much more precisr and easier to follow.

thanks

Generate an ER Diagram from ORM

rohabhatia — Mon, 23 Apr 2012 06:22:07 GMT

Hi... I am just trying out ORM and i created a small model... I was wondering how i could create an ER diagram directly from it.... I can use the Extension manger and get a relational view but no ER... Help would be appreciated.... Thanks

How to create ValueType Group?

Chiliyago — Tue, 10 Mar 2009 23:15:26 GMT

I have four ValueTypes that often get added to my Entity Types. These are: CreateDate, CreatedBy, LastUpdateDate, and LastUpdateBy. Can a group of these value objects perhaps called "ObjectTimeStamp" be created an then be applied to an EntityType? I would like to then generate SQL DDL that has those four ValueTypes as fields in my database. Thank you.

Updating an existing drawing with latest shapes and macros

Roger Cass — Thu, 08 Dec 2011 14:43:49 GMT

Since the Visio stencil has gone through numerous revision this year (all of which are fantastic improvements--kudos to Andy Carver), this leaves me with numerous diagrams that are based on previous versions of shapes and contained in files which do not have all the macros.

Is it possible to "upgrade" an existing Visio file to use the latest shapes and macros?

I understand that it is difficult to change the shapes on an existing diagram. I am sure the diagram I have been working on for a year now has at least 10 different versions of many of the shapes on the Document Stencil.

It may be easier to add macros to an existing document, however.

Any thoughts?

Ideas for Visio stencil based on v16 (and other thoughts)

Roger Cass — Sat, 03 Sep 2011 22:29:21 GMT

Based on my experience with v15 and the anticipated changes in v16 of the Visio stencil, here are some thoughts on how I use the stencil and some ideas for how it might be improved.

With the changes to Fact Types in through v16, I find it much easier to re-position and rotate Fact Types. Combined with Flip Vertical, Flip Horizontal, and Add/Remove Text Arrow, I find I can quickly get Fact Types in the orientation I want with readable text.

The are some "decorations" I associate with Fact Types, like role constraints (e.g. exclusive or), associativity constraints (e.g. acyclic strong intransitive). I also frequently use note text to annotate Objects and Fact Types. When I move the Object or Fact Type with which these items are associated, they do not move with it. If I forget to select them before I move the Objects or Fact Types, they get left behind.

It would be nice to find a way to anchor the constraints and notes to the things they are associated with. I realize the end points of the constraints can be anchored--I mean the symbol in the center.

Within the constraints of Visio, I am not sure how realistic any of those ideas are, especially when I might be asking for something like "always anchor them except when I don't want them to be anchored"--one of those mind-reader features.

I will also point out that due to this being Visio and a drawing tool, building a relationship requires the use of no fewer than six shapes (two objects, a fact type, two connectors, and a uniqueness constraint). This makes it laborious to create relationships quickly. That is the limitation of using Visio instead of NORMA in VisualStudio--I understand that.

If I think of other things, I will post them.

Applying a default value to a value type object

_Allan — Fri, 04 Nov 2011 01:08:20 GMT

When using ms-sql in design mode it is possible to set a "default value or binding".

It can be set to a value or a function call.

Is it possible to set this value when using NORMA?

__Allan

What is the difference between object role modeling and Entity relation daigram

Ahmadjan — Mon, 31 Oct 2011 08:20:36 GMT

Good day ,

Please help me to understand the difference between object role modeling(ORM) and enitiy relation daigram (ERD)

Thanks for helping

ORM Stencil v13+ auto-rotate of text

Roger Cass — Mon, 22 Aug 2011 15:20:15 GMT

I have to say that I don't like to way auto-rotation of text works in the Visio stencil version 13+. Specifically, I never use the style having the relationship vertical and the text horizontal. In my opinion that is a very space-hungry configuration and doesn't read well (ambiguous which way to read the roles when the text is orthogonal to the role boxes). In addition, for relationships with more than one short word, the relationship text has to be moved if the relationship is rotated, which is not easy.

I would really prefer that the text be rotated so that in the top of the text is always towards the role boxes except when the roles are rotated between +/-135 degrees (i.e. the text is "on top" of the role boxes), in which case the bottom of the text is towards the role boxes.

There are two "reversal" scenarios to consider:

First, the user wants to simply change the direction of the reading leaving the text as it is. The current context menu to add an arrow solves this problem.

Second, the user wants to completely reverse the relationship (i.e. a "flip"). I do this all the time when copying relationships to re-use them. A context menu that swaps all the connection points relative to the left-right centerline of the shape would do this (i.e. swap all the relative "x" coordinates). I do this in some of my custom shapes that have connection points.

In my opinion, automatically adding the text arrow as I rotate through 360 degrees "almost" works. Here is an idea for horizontal text.

As the roles rotate to nominally 180 degrees (past +/- 135 degrees), move the text anchor to the other side so it always remains on the bottom of the role boxes, and rotate the text 180 degrees. At the same time, add the reversal arrow. As the shape rotates back, move the text back and remove the arrow.

Vertical text is trickier because there is no convention in English for which way to orient vertical text (top-to-bottom or bottom-to-top). Add the convention that vertical text must always read top-to-bottom in the "natural" English reading, and we also add the constraint that the text must always be on the left of the role boxes. If we add this convention and constraint, then we can use the same rules for horizontal text with vertical text.

I'm not sure if I'd like this "left-side top-to-bottom" convention because I have to admit I use both top-to-bottom and bottom-to-top text in order to eliminate the need for a text arrow. I think I could live with it. This would constrain the relationship text to be on the left or bottom or the relationship and to always be read top-to-bottom or left-to-right for English.

Lots of comments, but I have to say that I CANNOT use the roles in their current form with the auto-rotating text. Until that is changed, I have to stick with the v12- shapes.

(On the bright side, I really like the results of my first test with the v14 macro for shadow corrections--great idea)

Roger Cass

How to change on update action on foreign key

szubia — Mon, 02 May 2011 16:53:19 GMT

I have a foreign key that has the ON DELETE NO ACTION ON UPDATE NO ACTION and I'd like the UPDATE to be CASCADE instead of NO ACTION. I know I can change the script manually to reflect that but I was wondering if there is any way to change that in the diagram. Thanks

Object Model auto fill requests

mnnoon — Mon, 20 Jun 2011 20:30:15 GMT

Hi,

I've been using the Norma add "New Page" tab at the bottom of the orm window and I noticed that you have to add items one by one when you drag and drop from the orm model browser. So I'd like to add to the wish list a feature to select multiple items from the orm model browser, and then move all those items you selected and move to the main orm window. Also I think it would be useful to add a schema name to the orm model browser to differentiate different parts of a model, and make it easier to sort model objects much like in the Sql 2008 management studio.

As a side note, I'd like to see a feature where I add a single entity and a depth feature that will retrieve all related items one to n levels deep. I think this was asked before, but not recently. This would definitely make this must more fun to use as it would just pull down all entities interested and then perfrom an auto format on those selected or the depth selected.

Thanks,

Marc

Can I model "a bottle of pills" as a predicate and then refer to either the whole bottle of pills or a specific pill in a bottle in another predicate?

sessaid — Wed, 15 Jun 2011 20:21:26 GMT

Hi all,

I am just learning about ORM and wondering if I will be able to model this example and the general case. I would like to have a predicate that stands for pills in bottles. I will then like to have a predicate that says that a pill is taken from a specific bottle. Will I be able to reference a pill in a MedicationBottle where "MedicationBottle" is the predicate MedicationBottle(pill, container) or something like that?

The idea is that medication bottles are created at the pharmacy (according to a prescription specification) by filling a container with medicine pills and then the medication bottle is used at home to get and administer a pill. I would like to model and track instances of all of these entities (pills, containers, medication bottles, uses of pills from a medication bottle, etc.)

This is just one example. The general case is that I would like to compose entities in one area of my model and then refer to certain elements of the composed entity in other places of my model. Is this doable in ORM?

Thank you,

Shahim

Graphically depicting derived fact types

Roger Cass — Sun, 08 May 2011 11:44:47 GMT

When working with business and technical team members who are experts in their respective domains, I often find that I need a way to express ideas familiar to those individuals or in common use in their domains, but which are actually derived fact types, not elementary.

I often leave these derived fact types in place (using Visio 2010 (v14)) because they are a useful tool for understanding the difference between current practice and desired future state.

In "the book", I noted the use of a colored background for role boxes in illustrating derived rather than elementary fact types. I have taken to using a light green color to indicate derived fact types. However, the application of that color is a bit of a chore in Visio, as each role box must be individually selected and the color applied--especially tricky in objectified fact types. I have not used NORMA in a couple of years, so I do not recall if that is built in or not.

While this offers the most flexibility to use formatting to illustrate some particular point, perhaps "derived fact type" is a common enough use case to warrant a context menu to shade the role boxes.

Does anyone else ever use the idea of derived fact types? What other methods are in use to illustrate this idea?

Thanks,

Roger Cass

Representing common consistency constraints

Roger Cass — Mon, 25 Apr 2011 13:57:06 GMT

Our use of ORM to help business and technical teams share a common language of concepts is taking off. ORM does just what I need it to do--help us focus on the concepts and not the details. I have run into a situation over and over, and I have never been able to model it satisfactorily. I usually end up adding a business rule note instead. Here is an example of where I think I need to show consistency constraints but am unsure how to do so. I have simplified this example, so please take it at face value and excuse my clumsy prose notation. Simplest (and not very robust) example: Company employs/works for Person. CompanyPerson is many to many. Company operates at/is for Address. CompanyAddress is many to many. Person is assigned to Address. PersonAddress is many to one. Consistency constraints are needed to enforce the idea that a Person must be assigned to an Address that is for the Company the Person works for. In this case, I believe I could show that the Addresses filling "Person is assigned to Address" must be a subset of the Addresses filling "Address is for Company". In a slightly more complex example, I objectify "Company employs Person" as "Employment", and objectify "Company has Address" as "Location". I then remove "Person is assigned Address" and replace it with "Employment occurs at Location", a relationship between the two objectified relationships. This new construct is arguably clearer and more obvious, but not the focus of this post. I still need to denote the following constraint: Employment and Location must be related to the same Company. How do I show this or even describe it? "If a Company employs a Person ('Employment"), and that Company operates at an Address ("Location"), then ...?" This is where I get stuck. I don't know how to visual show it on the diagram and don't know how to describe it in words as a business rule. One more case. Company has Department. Department has Employee. Company has Campus. Campus has Building. Employee works in Building. The constraint I wish to express is that "if an Employee works in a Building on a Campus for a Company, then that Company has the Department that has that Employee". This is similar to the first case except that now the consistency is enforced across multiple topological hops in the diagram. How do I show this? I hope my examples adequately represent the modeling scenarios I consistently see. So far, I have either left out the consistency constraint for clarity, included a verbose and quirky business rule, or tried to show (most likely incorrectly) the actual constraint. I would appreciate others' experience with these modeling situations.

How to represent a singleton value?

dportas — Wed, 20 Apr 2011 13:29:58 GMT

How should I properly represent an entity or value type that only permits a single value? For example in the following model CPI and ECI are supposed to represent single values - RateOfInflation being the designated rate at some point in time.

Formalization of normative knowledge for safe design by using NIAM/ORM

LHOSTE — Wed, 23 Feb 2011 15:14:46 GMT

I have published the following paper in 2003 : Authors : BLAISE J.C., LHOSTE P., CICCOTELLI J. Formalization of normative knowledge for safe design “Safety Science”, Special Issue “Safety in Design”, Vol. 41, n° 2-3, pp. 241-261, ISSN 0925-7535, Elsevier Science, Pergamon, mars 2003 Download : http://staff.ui.ac.id/internal/131287959/material/SafetyChapter-3MachinerySafety-1.pdf which relates to the use of NIAM/ORM to formalize standards and to help designers to better integrate these standards in their works. Contact me if you are interested ... Best regards. P. LHOSTE

how to model log info?

giacomo — Tue, 09 Jun 2009 10:13:03 GMT

In many existing database tables (especially for entities) there is often the same bunch of fields to log insertion or update of information (CreationDate, LastUpdateDate, CreationUserID, LastUpdateUserID, CreationOrganizationID, LastUpdateOrganizationID).

Is there an easy an elegant way to model such information for many different entities? I thought of subtyping a kind of 'loggable' entity but I'm not sure if it is conceptually right. Any suggestion? Thanks

Giacomo

Natural human input for model development?

JParrish — Sat, 23 Oct 2010 02:13:23 GMT

This is nothing more than a thought, aloud, to see what others may have also contemplated. The origin of this thought, is that during requirements gatherings in every enterprise or small office I've encountered, the only truly common theme is that individuals will quickly opt out of verbose language jarring into augmenting the discussion with visual models. These are most often informal ( concept ) --- relation --> ( concept ) but in one way or another, ER, UML, Mind Map, etc. people seem to prefer to use their hands and scribbling apparatus.

So to narrow the focus to ORM, and the means by which we construct an ORM model, consider for a moment: In one of these meetings, with a tablet PC in hand, would it be more efficient, or more "natural" to scribble the geometry that we know to represent ORM2.. and have a tool that could adaptively recognize the elements of the model? That is to say, as you draw, you aren't concerned with the validation of the model so much as the validation of the geometry (can the system accurately recognize the various shapes and intersections in a way that taxanomically add value)?

I've experimented a tiny bit now with Microsofts "Ink" libraries, but before even seriously considering trying to write a recognizer for simple ORM2 geometry, I was curious how useful something like this is.

In my mind, should something like this work nearly flawlessly, and benefit from hardware accelerated panning and zooming, it would be a very natural and viable alternative to structured input.

ORM & Relational Databases Surrendering to Scalable Non-Relational DB's

tralston — Wed, 22 Sep 2010 03:24:05 GMT

I recently started learning about ORM through Terry's book Information Modeling and Relational Databases (2e). It's a great resource and really satisfies my craving for sound logical structure in database modeling. On to the question:

In a small start-up business I work with, we are creating an online presence which by necessity needs, in my opinion, a very solid relational database. It tracks users, contributions of users, conversations between them, data facts, sources referenced by those facts, etc. I feel that ORM is a very capable vehicle for this. At the moment I'm leaning toward implementing it logically with PostgreSQL

The owner of the company, who funds all the development, is always looking for the next big thing on the internet to use in his plan for the company. Basically, if Facebook or Google does it, then so should we. He recently came across an article promoting the use of noSQL design. I'm not 100% familiar with it, but I do know that many basic tenants of relational design are not present (such as assuring concurrency, ACID compatibility, etc). He hasn't decided to go in that direction yet, but I know he'll want to talk about it, especially since several of the main social networking and microblogging sites have migrated to noSQL type architectures (like Cassandra for instance). I'm hoping someone here can give me some ammunition to help keep this in the "relational" modeling category.

As a side note, I do understand that if the site and user base grow to such a size as we hope, that it necessitates a conversion to another architecture. So my question is two-fold:

What are the advantages for a small to medium sized web company managing data online for several end users to design and maintain their databases in ORM and relational-type architecture?
If we do have to migrate later, has there been any successful attempts to adapt ORM to some of these more disconnected cluster database systems? If so, when would it be wise to switch over? Do the gains in speed and scalability really compensate for the loss of non-redundancy and possible data contamination?

I apologize for the long winded post, and appreciate any viewpoints or professional opinions on the matter. Thank you.

NORMA on Win 7 64-bit VS2008?

brianfarish — Tue, 14 Sep 2010 14:05:36 GMT

Should I be trying to run NORMA on a 64-bit Win7 platform under VS2008?

When I try to create a new ORM model file after the initial load of the NORMA plugin, I'm receiving an error message which states:
"Cannot load '...\AppData\Local\Temp\~vsC40D.orm':
Could not load file or assembly 'Microsoft.VisualStudio.VirtualTreeGrid,
Version=9.0.0.0, Culture=neutral, PublicKey=b03f5f7f11d50a3a' or
one of its dependencies. The system cannot find the file specified."

[:'(]

Model optimization

Dennis Johansson — Fri, 16 Apr 2010 13:19:46 GMT

Hi everybody!

I was taking a certification exam the other day and there was a small remark in my ORM model where I had an entity connected to a value type (True/False) using a binary role connector. The suggestion was to drop the value type and instead use an unary role connector to the entity.

My thougths around this is: If tis is true (which I assume it is), then there are obviously several ways of expressing the same thing in an ORM model. This implies that there are better ways and less better ways to model things.

Could it be possible to start thinking about some kind of model optimizer in order to reduce less better solutions in a given model? Since it is all based upon logic, there should be some kind of mathematical way of optimizing situations (like a query optimizer for databases or Karnaugh-diagram for digital circuits).

It would be a great tool in order to improve models as well as reduce unnecessary complexity in them.

FCO-IM Lexicalizing question.

michell — Tue, 06 Apr 2010 14:55:19 GMT

While reading the example model of converting an IGD to a relational database model (book "Fully Communication Oriented Information Modeling (FCO-IM)" found in the Library, section 4.2.1 "Lexicalizing in the Student-Project Case Study") a question arises.

In the lexicalizing step the normalization "student" is eliminated by splitting a role of a factype and injecting the student identifier "firstname" and "surname" for that role. In basis I understand this step, but when looking at the relational scheme (figure 4.12) two tables are created: student and preferences which include both the "firstname" and "surname" of students.

When I look at the database model, I would suggest to add a student ID to the table students. Which can be used in the table preferences, so that a reference can be made to the table students using one column "studentID". Why isn't that done/proposed?

Thanks for any suggestions,

Michel.

P.s. Thanks for the information on this forum and in the Library. It was already very helpful!

TimeStamp

halcwb — Thu, 08 Apr 2010 14:12:41 GMT

Does NORMA support creation of value types of type TimeStamp for SQL server 2008?

There is a Temporal Auto TimeStamp, but generates a regular DateTime.

Improving the NORMA UX

subkamran — Sun, 04 Apr 2010 17:27:39 GMT

Hi there,

While there are only 4 posts here, I figured the ORM Masters would reply to my lonely post.

I am currently taking Everest's Advanced DB Design class and have become pretty fascinated with ORM, albeit still a novice. That doesn't mean I can't dream.

I was thinking about starting a series of articles for beginners to get acquainted with ORM. I know there are those out there that are working on novice ORM books which I think will be incredibly helpful, but I think there could be more in the way of beginner tutorials that are accessible to a lot of people. I don't know how many of you follow online development sites like NetTuts, SitePoint, etc. but those are prime places to do a series like this. Screencasts, articles, tutorials, sample models, etc. Maybe even a wholly dedicated site ala http://asp.net (I was thinking: "Hooked on ORM").

Anyway, that was "Idea #1: Making ORM More Widely Available to Newcomers." The second idea is the hardest but I would like to be involved in it. That is to improve the UI and UX of NORMA. I was contemplating creating a web-based ORM modeler but the more I use NORMA the more complex it seems. Besides, why reinvent the wheel?

So, my questions are these:

1) Is NORMA separated enough (Data, Business, Presentation) to allow a different or additional presentation layer? Think web-based or perhaps a WPF application.

2) Is NORMA being extended to work with VS 2010? And, if it's not, I think it would be good to revamp the user experience for VS 2010 to take advantage of its richer graphical features. If it is, I'm interested in what's being done.

For me personally, I would be interested in pursuing one or the other, and to me it makes more sense to pursue 2) because there are a lot of pros to tying NORMA into the IDE (wizards for generating DDL, tie-in to Entity Framework, etc.).

Is the NORMA code loosely coupled enough to allow for a different approach to UI using VS 2010? For example, could I fork the project and create "my own" VS 2010 interface with all the existing code? My fear is that I wouldn't be very good at writing all the ORM logic myself (hence me not feeling too hot about rolling my own ORM modeling), but I do feel more comfortable creating a UI layer.

I don't consider myself any kind of UXpert, but I do feel NORMA could be improved in many ways... and it would be fun to try and contribute to that, even just on my own for my own learning.

Different roles

vkannel — Mon, 15 Mar 2010 06:12:07 GMT

Hey

I wanted to create model where Commander:

- has a signature right (only he can signe papers and there could be more then one paper)

- could be chief of exercise (one to many)

- appoints chief of exercise if he himself is not that chief of exercise (could appoint many chiefs)

Chief of exercise:

- could be commander (only one)

What I was not able to show in this diagram was that they both (chief and commander) have signature rights, but only one of them can signe it. Actually I am not sure that "Commander has signature right" is elementary fact at all, but let's assume that there could be fallow on with fact "Paper has signature". So the entity could be "signature" with entity type signature right....or?

Is there any simpler way to show Commander and Cheif realationship?

V.K

Help with an Equality Constraint

PeterC — Tue, 26 May 2009 06:58:47 GMT

Hi,

I'm hoping someone with more experience with ORM than me, and/or a better grasp of logic, can help with the following scenario (which is part of an ORM model with the Objects' and Facts' text changed - hence some of the Facts may appear a little strange).

I have a Cat Show where people may show their cats. Each Person must sponsor a Pennant. The constraint that I want to show in the model is: the Colour of the Pennant sponsored by a Cat's Person must be the same Colour as the Collar worn by that Cat. A diagram is attached.

I have tried a number of variations of the constraint, and although the verbalisations of some are along the lines I'm after; to me, none are clear enough to accurately describe the desired constraint. For examples, I can get:

"For each Colour, that Colour describes some Pennant if and only if that Colour describes some Collar." [1]; or

"For each Colour and Person, that Colour describes some Pennant if and only if that Colour describes some Collar." [2a]; or
"For each Colour and Cat, that Colour describes some Pennant if and only if that Colour describes some Collar." [2b]; or

"For each Colour and Cat and Person, that Colour describes some Pennant if and only if that Colour describes some Collar." [3].

[2b] appears the most succinct, but I don't know whether it is correct and sufficient. Thoughts, anyone?

Thanks, Peter

ps If the picture doesn't appear after this is posted, can someone tell me how to include a picture? (I've tried paste from Word and paste from clipboard and "Insert/edit image" button, and can't see any results.