On Wed, Aug 7, 2013 at 11:38 PM, Alban Hertroys <haramrae@xxxxxxxxx> wrote:
On Aug 8, 2013, at 4:11, Sergey Konoplev <gray.ru@xxxxxxxxx> wrote:Or, instead of attempting to reference all child nodes from the parent, reference the parent node from each child node.
> create table node as (
> id integer primary key,
> r integer, s integer,
> children integer[] element references node
> );
>
> so you could download 9.3rc2 and experimant with it.
>
> Now (on <=9.2.x) you can create the table without FK
>
> create table node as (
> id integer primary key,
> r integer, s integer,
> children integer[]
> );
>
> and check integrity by triggers.
That's been supported in PG versions like forever and can be queried fairly efficiently using recursive CTE's since PG 9.
If you do this, have a position number, and use that for ordering. You need some sort of ordinality here.
Best Wishes,
Chris Travers
Alban Hertroys
--
If you can't see the forest for the trees,
cut the trees and you'll find there is no forest.
--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
Best Wishes,
Chris Travers
Efficito: Hosted Accounting and ERP. Robust and Flexible. No vendor lock-in.
