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Issues with Ordering and Positioning of AF Element Attributes

Question asked by acarlini548b on Apr 13, 2016
Latest reply on Jun 24, 2016 by Roger Palmen

One of the main concern I've got during the implementation of PI AF is the representation / visualization of AF Element Attributes in the Clients and in the responses from the various Interfaces ( ODBC/JDBC, Restful web services .. etc ).


In many other applications we use , for example to manage product specifications, recipes, etc, the grouping and positioning of attributes/variables within an entity must respect certain rules, and the application provides a sort of "ordering field", that is automatically updated according the position of the attribute or attribute group / category when you physically create that attribute/variable within an element ( or element template ).


Now, in my specific use case, my element is an instrument ( or device as well ) that has attributes with three different categories that must be represented always in a specific order :

  1. Design parameters
  2. Engineering parameters
  3. Operating conditions / variables

Within this categories the attributes and sub-attributes must always be represented in the same order, ( as you enter it in the template ), and not by name.

In other applications I own and manage this kind of discussion started more than two decades ago, then it was implemented so far, and today it has been promoted as a best practice for the most common scientific and business application in the market.


I would like to know how some of you solved this issue without doing a very old and bad practice : putting numbers or alphanumeric characters in front of an element name, category name or attribute name.


Why we can simply have an ordering number field/property at least for category and attributes, that can be used for automatic sorting ( i.e. in sortField for PI webapi or PI SDK ? )


Thanks in advance for your comments and contribution for this topic.