Attributes vs Tag Values

[ducatiross]

I want some advice from others who have considered this topic before.

When I am creating objects, say in ArchiMate to represent roles, business functions, principles, goals etc etc, I want to be able to define attributes to store things of importance that I then want to be able to query. For instance, I would like all roles to have 4 characteristics to detail :-
- Basic salary (type : decimal)
- Salary grade (type : char)
- Number of roles of this type needed (type :integer)
- Full Time Equivalent (type : decimal)

Then, whenever I create a role, I want to be able to have these characteristics available and set their values.

After entering all this data, I would like to be able to gain access to it to answer questions such as :-
- what is the total salary costs of the finance department ?
- how many roles of grade E have I got and what departments are they in ?
- how many people are assigned to roles such that their actual total workload is more than 1 FTE ?
- Give me a list of all the people, their role and their FTE for the Production department.

Now, leaving aside the question of navigating the tree structure to identify these relationships and connections (BTW has anyone got a good tree walking methodology for EA ??!!) what do you suggest as the best way to implement this so that it makes it easy to both assign the characteristics in the first place across all objects of that type and then get the information out ? Should I:-
- use the Attribute option under the Details section of the object
- define TAGS for each characteristics then add these to the objects as required

Attributes seem to be the purest method from a methodological point of view, but I can't seem to find a way to define a set of Attributes then have these made available to all objects of a certain type.

Tags seem to be a more pragmatic way of easily adding the same tag to multiple objects, but I'm not sure if I can then use them easily in reporting and answering the questions.

So, Attributes or Tags - what wins ?

If anyone has struggled with this before and come to a conclusion, I'd be grateful to hear from them.

thanks

[Geert Bellekens]

That depends whether you are modelling on a meta level or not.

If "Role" is an element from your meta model, which you instantiate as model elements in your model then you use attributes on the meta model level (UML profile) which translate to tagged values on the model level.

If however you consider "Role" as a (abstract) concept in your specific model, then you model it as attributes on the abstract Role element.

In this case it definitely feels like they should become "regular" attributes.

What you can use to determine this is ask you the question: "Do I know this at design time?"
If you will only be able to fill them in at runtime then they are definitely attributes.

Geert