Messages

16

General Board / Re: Logical Data Modelling in SPARX

« on: October 21, 2018, 01:10:10 am »

Just a few 2c

A logical data model is implementation-independent (as-in: RDBMS independent) by definition.  If there is a RDBMS-specific item, then it's a physical data model.  The idea of logical data model is high reusability and easy extension to whatever technology is chosen for implementation (+robust against mid-project IT architecture changes)

A UML class diagram is a superset of data model (i.e. a data model + other stuff that you can simply ignore if you want to do ERD).  Any leading data modeling tool like ERWin or Sparx (professional and higher if I remember right) lets you choose what notation to use (IE/Crow's Foot or UML).  Yes UML handles PK/FK and FK migration just fine as stereotyped attributes.  You can also show triggers and indexes a stereotyped operations.  You can easily handle relationships with composite foreign keys (if that's what you mean by relationships between multiple attributes).

You can make conceptual, logical and physical data models easily in Crow's Foot.  Just click the notation you like by clicking on the Diagram options in Sparx.   There really is no significant difference in what you can do with UML or Crow's Foot / IE notation (google for details).

You can reverse/forward engineer from most leading DBMS with Sparx.  It's not as easy and fully featured as ERWin , Embarcadero etc; also relationship management is a little clunky, but anyway Sparx gets the job done at lower cost than dedicated data modeling tools.

There is a documentation PDF in the Sparx reference section that explains how to do all above.

Good luck!!

17

General Board / Re: Browse for diagram cannot select class, component and other diagrams!

« on: October 21, 2018, 12:55:02 am »

Mr QWERTY Sir, on my machine Start - Search - Browse for diagram, a "Select a diagram" window opens, Visible Diagram Types: there's a drop down box With only options being <All>, InteractionOverview, Sequence, Communication and Timing.  So for example I cannot filter only a Class or Use Case Diagram -  they don't appear in the drop down box.  Any suggestions welcome because I have a bajillion diagrams and I need to search them quickly.  Thanks!

18

General Board / Re: Browse for diagram cannot select class, component and other diagrams!

« on: October 19, 2018, 03:17:12 pm »

Still struggling with this...

Anyone has a fix?  Thanks

19

General Board / Browse for diagram cannot select class, component and other diagrams!

« on: October 04, 2018, 01:15:13 pm »

Hello version 13.0.1310 on WIndows 10, I have a custom MGD loaded but I don't think it makes any difference.  Start/Search/Browse for diagram, View Diagram Types the drop down menu only llows me to filter interaction overview, sequence, communication and timing diagrams!  I have plenty of class, package, component diagrams etc. and they show in the broswe diagram window bus they canno be filtered via the drop down menu.  Is this a bug or am I doing something wrong?   Thanks!

20

General Board / Re: Need help for correct ball and socket representation in component diagram

« on: September 12, 2018, 09:44:33 pm »

Hello - quoting myself below: the more immediate question is, does Sparx EA deviate from the UML 2.5 standard for interfaces?  Or did I miss something

Anyone knows?  Simon M?  Thanks!

Hello I have version 13.10 and I have a question about interface representation in component diagrams.  I think the correct UML 2.5 procedure (for example this works in Eclipse Papyrus UML modeler) is
- Draw component 1 and component 2
- Draw interface 1 and interface 2, right click - use circle notation
- Add <<Realize>> dependency from component 1 to interface 1
- Add <<Use>> dependency from component 2 to interface 2.  Interface 2 should be displayed as a socket (open semicircle), showing it's a required interface
- Add dependency between interface 2 and interface 1.  Done

However, well there is no <<Use>> dependency in the toolbox (you can find it in the dependency properties menu under Stereotypes) and the ball does not turn into a socket when connected via a <<use>> dependency. 

Is Sparx inconsistent with UML standard?  Or am I doing something wrong.

p.s. I know about the Exposed interface - right click and choose provided or required and the assembly connector, but these seem like a bit of a kludge (convenient at times, but still not a UML 2.5 compliant interface).  For example I can add attributes to the Expose interface; I can't differentiate between provided and required interfaces in assembly connector, and other issues.

Couldn't find anything useful in the documentation.  If anyone has ideas please share thanks!

21

General Board / Re: Requirements to ERD Entities, Attributes and Relationships

« on: September 11, 2018, 11:50:45 am »

Double click on class diagram - connectors - connector notation - select Information Engineering you get a very decent crow's feet notation.

For good Crow's Feet you can also look at DB Designer Fork (sourceforge.net) or MySQL Workbench (Oracle.com).  Both open source and both very capable.  Why would anyone want to use Oracle Data Modeler out of their own free will is beyond me.

diagram properties | Connector | Connector Notation

I don't see this option in "Diagram Properties."  I am using R14.
My data modeler refuses to use Sparx due to the way relationships are represented. He wants crows feet. He downloaded Oracle data modeler and is happy.
Doesn't make me feel good about the $2K we spent on Sparx licenses.

22

General Board / Re: Show several instances of the same element on one diagram

« on: September 05, 2018, 05:51:56 pm »

Mixing Archimate and UML IN THE SAME MODEL is not a good idea IMHO.  Each has its place, but their metamodels don't play nice together, so.... good luck???

Richard - for me the challenge is that we are using Archimate as well as UML.
From an Archimate perspective, there is no such thing as an instance (or alternatively an element is the instance depending on how you look at it).  The overhead and implications of creating children and generalisations make that quite messy, and breaks the model (in the sense that there are multiple things representing the same thing).

To be clear, I am sympathetic to the argument that whilst putting multiple elements on a diagram to handle layout challenges would be convenient, it's also a bit of a cop-out. However we have use cases where we genuinely need to represent the same element multiple times on Archimate diagrams due to the inherent structure of the type of diagram.  One example is 'box in box' diagrams of a hierarchy, with overlays of a different concept.  For example - a Capability Map (box in box) with an overlay of applications, projects, strategies etc  Usually the overlaid concept has elements associated with multiple capabilities, so needs to appear multiple times; the entire point of the diagram is to see where everything falls, how many for each capability, where there is overlap and duplication etc.

23

Bugs and Issues / Re: V1426; Why is it not possible anymore to have elements outside of a diagram fram

« on: September 05, 2018, 05:48:52 pm »

Yes that's my understanding.
Also to note "The elements of UML 2 style", point 42, Avoid diagram frames.  If you can, not having a frame at all is often a good idea. Although the UML standard seems to be driving in opposite direction (OK UML is not perfect, but still very good!)

24

General Board / Need help for correct ball and socket representation in component diagram

« on: September 05, 2018, 02:00:35 pm »

Hello I have version 13.10 and I have a question about interface representation in component diagrams.  I think the correct UML 2.5 procedure (for example this works in Eclipse Papyrus UML modeler) is
- Draw component 1 and component 2
- Draw interface 1 and interface 2, right click - use circle notation
- Add <<Realize>> dependency from component 1 to interface 1
- Add <<Use>> dependency from component 2 to interface 2.  Interface 2 should be displayed as a socket (open semicircle), showing it's a required interface
- Add dependency between interface 2 and interface 1.  Done

However, well there is no <<Use>> dependency in the toolbox (you can find it in the dependency properties menu under Stereotypes) and the ball does not turn into a socket when connected via a <<use>> dependency. 

Is Sparx inconsistent with UML standard?  Or am I doing something wrong.

p.s. I know about the Exposed interface - right click and choose provided or required and the assembly connector, but these seem like a bit of a kludge (convenient at times, but still not a UML 2.5 compliant interface).  For example I can add attributes to the Expose interface; I can't differentiate between provided and required interfaces in assembly connector, and other issues.

Couldn't find anything useful in the documentation.  If anyone has ideas please share thanks!

25

Bugs and Issues / Re: V1426; Why is it not possible anymore to have elements outside of a diagram fram

« on: September 05, 2018, 12:30:18 pm »

I don't think that's how diagram frames work in UML 2.5....  boundaries maybe, but not frames

26

General Board / Re: Show several instances of the same element on one diagram

« on: September 05, 2018, 12:27:57 pm »

What's wrong with my initial proposal.
If you want to have different instances of one classifier in a diagram, go ahead and knock yourself out
If you absolutely-positively must have same instances of one classifier in a diagram, create children of the classifier using generalization.  I's the same as using a placeholder / bookmark / virtual thingy but it's 100% UML compliant... no gimmicks needed.

This is really a UML question, not a tool question.  I don't think it makes sense in UML to have multiple instances of the same classifier in a diagram, and if absolutely-positively need to, the correct way to do it is with a generalization (duplicate element IS-A original element).  EA implements the UML standard correctly by not allowing 2 of same classifiers in a diagram. 

I'm pretty sure there's nothing in the UML specs that says you can't put an element on a diagram twice.
In fact UML says very little about what you can or can't do on diagram.

But I don't understand your point about generalization. If I wanted to put a an action on a diagram twice, how could generalization help me? I don't even think generalization is allowed between Actions.

Geert

27

General Board / Re: use case non human actor

« on: August 28, 2018, 08:30:41 pm »

The best way would be to define a stereotype for the actor; it will appear on the use diagram as text
Comments are also a good way to display this kind of thing.
I do not want to know why you need an actor with a blindfold - maybe it is a ninja turtle or something?  Anyways let 10,000 flowers bloom said a famous guy....

hello
i have find on use cas an actor with blindfold
how i can set a new actor for having blindfold ?

i don't find where i can set a property for having this

thankjs

28

General Board / Re: Requirements to ERD Entities, Attributes and Relationships

« on: August 17, 2018, 08:35:44 pm »

A ERD is simply a class diagram with a specific profile (Crow's foot notation, stereotypes for primary/foreign keys, triggers and constraints are represented as operations etc.)  Anything you can do with a ERD you can also do with a class diagram (there's whole books on this subject on Amazon).

That's not quite true. ERD is elder than UML (at least the UML we use now). But UML can mimic ERD by means of a profile.

q.

Hi qwerty, so seems like you agree with what I posted, and do I sense a bit of impedance today?

29

General Board / Re: Requirements to ERD Entities, Attributes and Relationships

« on: August 17, 2018, 11:07:48 am »

Hello Dana

A ERD is simply a class diagram with a specific profile (Crow's foot notation, stereotypes for primary/foreign keys, triggers and constraints are represented as operations etc.)  Anything you can do with a ERD you can also do with a class diagram (there's whole books on this subject on Amazon).

I remember years back the OMG looking into requests to adopt ERDs and concluding that UML already has full capability to do what ERDs do, so nothing to be gained.  The main issue is programmers proficient in UML not liking data modelers proficient in ERD and very much vice versa (look up "object impedance").

Anyways a data model (in whatever notation, class diagram or ERD) is an excellent way to capture requirements because you can efficiently and precisely rationalize key concepts (entities and attributes), business rules (relationships and cardinality; also datatypes and domain checks) and other qualities into one simple model that can summarize hundreds of different requirements from dozens of business processes and IT systems. 

The best way to learn how to do it is to pick a methodology and practice, practice practice.  Most methodologies recommend PLAIN TEXT to capture requirements, then transfer the text to comments on said entities, attributes and relationships.  Sparx tagged values and CSV import/export make this very convenient. 

Good luck!

Phew. Going directly from requirements to a data model is like having the cake from the flour on the table. Requirements -> Use Cases -> Conecptional Class Model -> Concrete Class Model/Data Model would be the way to go.

q.

In this case, the customer has provided a specification of what data is to be in the database. This task is to simply produce a conceptual data model representation of that specification and the tracing to requirements (specification) is to make sure I have full coverage.

I am curious about "Conceptual Class Model" versus ERD Diagrams in EA. In the past, I have done my data modelling in Class Models but coming back to the tool after about 5 years I discover the ERD Diagram feature. To be honest, I am not quite sold on the ERD Diagram yet. Is there a good resource on the pros and cons of each approach and when/why to choose one over the other?

30

General Board / Re: Lollipop vs. Interface

« on: August 14, 2018, 10:42:50 pm »

What qwerty said.  It's the UML 2.x standard... not as use friendly as UML 1 in this case, but standards are standards...