Question

In MySQL, is it bad to have a table structure like the following…

Table stuffA
ID

Table stuffB
ID

Table superStuff
ID
type
stuffID

…where depending on the value of superStuff(type), superStuff(stuffID) could reference either stuffA(ID) or stuffB(ID) ?

Thanks, in advance, for your help

Answer 1

I think you mean the other way around:

Table stuffA
ID
superStuffID

Table stuffB
ID
superStuffID

Table superStuff
ID

Besides you don’t need the type attribute because it is implicit when you query one table or the other.

NOTE: I’m assuming you also have other fields on the tables and that you’ve ommited them in order to make a minimal example. If this is not the case, probably you wouldn’t need a hierachy there.

This answer might be helpful in understanding this.