Re: Tables Referencing themselves As Foreign Keys

Tony,

That'll work, but you have to mind the first row/toprow you insert.
Will it have no parent (make the field nullable) or will it be its own
parent (you'll have to test whether that works, I don't know, foreign
keys are deferrable, so it should be possible if you specify that).

Best regards,

Arjen

Tony (Unihost) wrote:

> Hi,
>
> I'm still new to this so if I'm sounding dumb or my premise is flawed
> please forgive me. I have a DB design which contains a table which has
> categories, each category has a parent category, and is recursed until
> the top category is reached, in order to create breadcrumbs. Is there
> any problem with using foreign keys to reference the same table? So a
> when category is added the CatParent MUST be present as a CatID
>
> CatID - Serial
> CatParent - int4 - References CatID
> CatName - Text
>
> Am I likeley to come unstuck with this?
>
> Cheers
>
> T.