patrickmcginnis59 10839 (4/26/2013)
This is an interesting case, so I'm guessing that it really depends on how important the functionality of the foreign key constraint is for your needed functionality. If it is really important, then I would lean toward having a phone table for each parent table that needs to have zero or more phone numbers linked to it. If you wanted to report on all phone numbers, you could use a union query of some sort.
There are other object types that cannot be derived from [Person], such as Offices, Vendors, Trustees, etc. which still own [Phone] numbers. For the purposes of this discussion, let's assume that it is not an option to abstract these business objects to a higher level and bind phone numbers at that level.
G.