Re: Can a field be a primary key as well as a foreign key?

Andrew Snow wrote:
>
>
> Can anyone see any problem with the following, practice?

No problem at all. With that setup there can never be a
subchild without the matching child, even if the parent
exists. If a child is deleted, it's subchildren follow, no
need to touch the parent. If that's the relationship of the
data, go ahead.

Jan

>
>
> CREATE TABLE parent (
> foo SERIAL PRIMARY KEY
> );
>
> CREATE TABLE child (
> foo INTEGER PRIMARY KEY REFERENCES parent ON DELETE CASCADE,
> bar TEXT
> );
>
> CREATE TABLE subchild (
> foo INTEGER PRIMARY KEY REFERENCES child ON DELETE CASCADE,
> bar2 TEXT
> );
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>

--

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