I am using CR10 SP6 (with automatic database linking disabled in the registry).  My report manually links an Oracle with a DB2 database.  After much searching on the "join type cannot change" error message, I have found a single post in this forum (?TID=1702) that mentions in passing that such a link can only be done for a single field.  Is this right and can anyone point me to the 'official' statement of this?  Thanks!