I do not know if that is a necessary requirement. But when it is then you still can do it, but this query should be modified whenever another table also...

Yes, perhaps NotesHeader is a better name, since Notes gives you the idea that it contains the notes(text) itselves, which is not the case. And then the NotesItem table can...

5th Solution:

Add two tables for Notes:

Notes table

------------

NotesID int PK

NotesItem

------------

NotesItemID int PK

NotesID FK (to Notes table)

Memo

Etc

And add for each table (WorkItems, Contracts, Suppliers, etc) that must support Notes an additional column...