I am trying to build a model for the HL7 messaging structure. This structure makes extensive use of structured types as domain objects. I have figured out how to model these in SQL Server Data Modeler but I am not sure if the structured type definitions would transfer to other database types (non-Oracle). I need to use this model in SQL Server also. I have noticed that structured types do not appear to be supported in tools like Erwin which makes me even more suspicious. Does anybody have experience dealing with structured types outside of Oracle? Are there other approaches that could be used to model something like HL7 without structured types?