You can't. The easiest way is to create the third table with a column for
each FK. If you don't want to do this, then triggers are your only option
Another alternative is to create a fourth table that has the same general
structure. The 3rd is devoted to rows associated with table A, the fourth
is associated with rows from table B. You could then define a view that
unions the two tables if you need to see the rows together.
"Bill" <com> wrote in message