The mandatory nature of the relationship is based on the mandatory nature of the underlying DB attributes.
Ie, if PAINTING.ARTIST_ID is mandatory, then the relationship Painting.artist is also mandatory and must not be null. On 3/23/07, Roja Buck <[EMAIL PROTECTED]> wrote:
All, I am a little new to databases so I apologise if this query is particularly incompetent. I have created a series of tables all of which are related to one central table with that central table having relations of one to many with the rest of the tables. The problem I have however is that I want to be able to specify which of the fields (i.e. relations) are required within that central table. I understand how to do this for general attributes within a table however I see no way to say that a relation is required. Am I misunderstanding this fundamentally or simply missing something? An example of this using the examples in the getting started guide would be adding an artist who had not yet created any paintings, or similarly a galley with no paintings. Roja
