The ORM Foundation

Hello Clifford, Forgive me my ignorance. I wasn't even aware of the existence of two separate versions of NORMA. Frankly, I am not necessarily enamoured with graphical notation only, so I don't necessarily care so much about a tool, as much as about the modelling language itself (its axioms, theorems etc.). My experience with ...

 Hi Ken, The model as it is now, comes much closer to the specification we started with, however it is not exactly what I was trying to accomplish. A great model should in principle be able to express all that is needed to derive the desired implementation. Whether that derivation is algorithmically implemented in a tool is a different ...

Hello Ken, Thank you for your example. I greatly appreciate the effort you put into answering my question. Let me start with a practical note: I get "Access denied. You do not have permissions to perform the requested action", when trying to download the files you created (I was logged on when trying to download).  Now to the ...

 Hello Ken I am looking forward to see what you are brewing, and thanks for the information about VS.  Niels   

Hello Ken, Thank you for your quick response to my question. Back in the 1990s, I worked for a company where we used Infomodeller for our database design, and I very much liked the approach. Ever since I have used the schema techniques on a more informal basis (white board drawing, pen and paper design), but haven't yet caught up with the ...

Postgresql since version 9.0, supports the notion of exclusion constraints, which are a generalization of uniqueness constraints. Exclusion constraints are particularly helpful when dealing with datatypes like ranges, where equality is not necessarily the most helpful operator.  With exclusion constraints one can state that a certain ...