We are using MEGA for TOGAF - while working with the TOGAF standard meta model we came up some questions regarding the Data Entity (DM) in MEGA:
1. How can I directly create Data Entities within MEGA? Creation of Entities (DM) is not shown as option when clicking "New" on a library. Thus I always have to use a workaround by adding Entities to a Package (which is defined as "TOGAF Logical Data Entity")
2. When decomposing Entities, MEGA automatically creates a "class" instead of referring to the data entity. Here I'm on the TOGAF option -> Decomposition -> Decomposes. What I need is to show a hierarchical relationship between Data Objects. However, when using the explorer view on a data object, I can navigate to the parent data object (type Entity (DM)). On the parent (and only in the explorer view), the corresponding child element is named as Entity DM. For me this looks inconsistent.
Thank you in advance for any helpful advice
Hello Mr Peters,
In fact, there is no (New) option from Library to create Data Entity. From Library, you must create a Data Model that is a set of Data Entities and used to represent the structure of a system.
You can add Entities in the (Objects -> Entities) Tab of Data Model Properties box.
For the 2nd question, I think that is a bug. When decomposing Entities, MEGA must create a Data Entity instead of “Class”. a fix will be planned for the next CP.
Dear Mr. Noury,
thank you for your supply. Regarding the first issue, I still believe that the way entities are handled within the repository does not express the sense behind TOGAF. Reasoning while following a strict TOGAF oriented approach:
1. Data Models are designed being part of the "Logical Data Entity" which is an extension to the TOGAF core content Meta Model. Thus it is not part of the TOGAF core meta model which is typically the model used in an architecture context where the project team only has a simple view on data objects.
2. "Data Objects" are independent of any data model. Thus, from the architect's perspective, the attachment to a data model is inconvenient since it suggests a technical (data base) driven approach. From the users perspective I would also expect that all business related "Data Entities" are accessible in my repository in a folder named "Data Entities"
3. When only working with TOGAF Data Entities, e.g. while defining relations to Business Services oder Logical Application Components, I always deal with "entities (DM)", but not with the data model itself (which is not known to me and which I even do not need to know). Thus it is not understandble why certain artifacts can be directly created and accessible in the repository.
However, in project work we create data entities via the excel importer or the work around you have described. From a feasibility point of view I still suggest that this way is not consistent nor convenient for any architecture driven user. Currently, it typically ends up in discussions with our tool users why certain objects can be directly created from the repository while others are hidden in some sub options when they are expected to be in the main repository. Thus I still come to the conclusion that the current approach is too inflexible when working with data objects. However one can live with the suggested workaround when creating data entities.
Thx in advance