Re: Non Identifying Foreign Key Relationships

On Mon, 24 Mar 2003, Karen Grose wrote:

> I am in the process of upgrading to Postgresql 7.3.1 from 7.1. While
> testing the results of the conversion, I have run into an issue with
> establishing non-identifying or optional foreign key relationships.
>
> 1) My child table definition contains a foreign key that references the parent primary key
> 2) The child table column referencing the parent is not part of the child primary key
> 3) The child table column referencing the parent is defined with NULLS allowed
>
> The test that I performed tried to load NULL values into the column
> and it failed with a referential integrity violation stating that the
> parent must exist. How do I accomplish creating this type of
> constraint within Postgresql version 7.3?

That should work I think, can you give a standalone example script?