> I hope Helen or someone will tell me that I was wrong when I
> said that separate databases cannot be joined in a query, but
> I think I've read it from this list before.

As Helen already said, you are correct. Each dataset represents a
specific query, and belongs to a particular connection/database.

The reason for posting is to highlight that master/detail
relationships between client datasets are entirely client operated.
There is no reason why a master/detail has to be one-to-many; it can
also be used for one-to-one relationships.

Simply setup one dataset querying one database/connection, and another
querying the other (both connected to the same transaction). Setup
the relationship between them using master/detail facilities and let
IBO take care of the rest.

HTH

Geoff Worboys
Telesis Computing