On 24 Apr 2003, Hadley Willan wrote:
> Thanks. It's pretty much what we'd thought then. But sometimes you like
> to check these things out to avoid the "doh!" that comes later.
Well, one other workaround is to make a table that has only the ids and
then have each of unit, boats, cars, etc... foreign key an id to that.
Then at least you can foreign key to the id table, but that doesn't help
you with the allowing dups between boats and cars.