From: silly sad <sad@bankir.ru>
To: Achilleas Mantzios <achill@matrix.gatewaynet.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Table Design for Hierarchical Data
Date: Wed, 07 Apr 2010 11:53:00 +0400
Message-ID: <4BBC39DC.6050502@bankir.ru> (raw)
In-Reply-To: <201004071000.15529.achill@matrix.gatewaynet.com>
References: <n2i5ab13581004061033j4ed25734xd0504cb95a1fc092@mail.gmail.com>
<201004071000.15529.achill@matrix.gatewaynet.com>
On 04/07/10 11:00, Achilleas Mantzios wrote:
> Column | Type | Modifiers
> ---------+-----------+---------------------------------------------------------------------------
> id | integer | not null default nextval(('public.paintgentypes_id_seq'::text)::regclass)
> name | text | not null
> parents | integer[] |
> The parents of any node to the root, i.e. the path of any node to the root are depicted as
> parents[0] : immediate parent
> parents[1] : immediate parent of the above parent
> .....
> parents[n] : root of the tree
what this schema gives?
(1) the parent branch in one select.
what else?
nothing.
compare it to a nested-tree
id | integer | NOT NULL
name | text | not null
parent | integer |
l | numeric
r | numeric
(1) parent branch in one select
(2) child subtree in one select
(it makes a sence!)
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To: pgsql-sql@postgresql.org
Cc: sad@bankir.ru, achill@matrix.gatewaynet.com
Subject: Re: Table Design for Hierarchical Data
In-Reply-To: <4BBC39DC.6050502@bankir.ru>
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