I've found when I'm using Oracle that I can do a quick compare between databases by db link.
set up the Oracle Net Client path in tnsnames,
then create the dblink using a user with dba rights in the other.

ex
select owner, table_name from dba_tables
minus
select owner, table_name from dba_tables@dblinkname

From what I know, In DB2 with federated...
I need to use a distinct and static nickname for each object.
Or I can do a path-through query...but that is just for one server at a time.

Is there a way to get the effect of a pass-through, but also have access to the current too?

ex.
select tabschema, tabname from syscat.tables
minus
select tabschema, tabname from syscat.tables (as pass-through reference)

Right now, I'd have to setup a nickname for each and every dictionary view I'd want to query otherwise...a bit tedious.

Any input would be appreciated.

I just make export the relevent syscat tables (tables, columns, indexes, etc) and then load them to new tables in the other database using a different schema name (not syscat) and then write some SQL to do the compare.