Dear Liangbing,
unfortunately extensive error messages shown in the Webclient are sometimes incomplete due to space restrictions. Can you please post the complete error message as appearing in the DMX server log. Without it I can’t say what the actual problem is.
Note that the very Organization-Person-Role scenario you describe is already part of the DMX standard distribution. My advice is to play with the standard model first, that is creating content. Then start investigating how the standard model is build. You can do all that interactively in the Webclient.
Associate a Person with an Organization. Result is an association of type “Organization Involvement”. That association further qualifies the person-organization relationship by “Role” (e.g. “Founder”, “Employee” …). Note also that you can introduce new roles (“CTO”, “CFO”, …) just by typing in the form (when the association is selected, see screenshot). You’re not required to define any new topic type for that. If a person occupies several roles in the same company create several Organization Involvement associations. If the existing model is not sufficient you can extend it e.g. by adding further child types to the “Organization Involvement” association type and/or to the “Person”/“Organization” topic types.
According to DMX’s “semantic” approach it’s a good idea to use the types that exist already. E.g. one would not define “Manager” as a topic type because a manager is a person, and topic type “Person” exists already. Semantic-wise “manager” is not a quality of a certain person per-se, but of that person’s relationship to a particular organization. The same person can play different roles in different organizations.
Modeling is a tricky subject in general, and modeling in DMX definitely has its particularities. Do you think the DMX docs could be improved in that area?
BTW: for new questions please start a new forum topic (and add an informative title to it). This will help others to find and refer to relevant forum information.
Thank you for the question!