How to use different Postgres schemes

[Adrián Quintana]

Hi All,
We have been testing RDB and SDB. We have understood the general 
behavior but we have some doubts. We are developing an Electron 
Microscopy Software. We have a base ontology that never change (where 
the types and programs are defined) and which is the base of the 
application. Each new project in the application will have its own 
data/ontology based on it. This project ontology will be update and 
modify several times. We want the project information to be stored in 
each own schema or table. These new project ontologies will have to be 
linked with the base ontology in order to define the different objects 
(store the kind of data and the programs that have been used).
We have been looking for scheme support in RDB and SDB but we have not 
found any information. Is it possible? How can we do this? If not, has 
TDB or any this feature?
Best regards,
Adrián
PS: We have already read the mailing list entry non-SQL databases and 
combining SDB and TDB models which explains similar problem but we have 
not understand the procedure...