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Re: [Gnumed-devel] use of PG inheritance in GNUmed
From: |
Ian Haywood |
Subject: |
Re: [Gnumed-devel] use of PG inheritance in GNUmed |
Date: |
Sat, 13 Mar 2004 22:20:04 +1100 |
On 13 Mar 2004 12:15:09 +1100
Tim Churches <address@hidden> wrote:
> In other words, the inheritance of columns
> and rows operate in opposite directions, which doesn't seem very useful
> to me - or at least it isn't for my purposes (unrelated to GNUmed). Does
> this characteristic of the inheritance cause problems for GNUmed, or is
> it an advantage.
Back-inheritance of rows to the ancestor is useful: when we implement a "notes
browser" we want to search all
the clinical tables for anything that happened during a particular time, with a
common ancestor we can do this in one query.
(as opposed to ~10, more as we add features) Problem is, this query can't
access the descendant columns that contain all the
interesting data. We will probably need a free text "comment" column in the
ancestor, populated by a trigger for each descendant table.
Ian
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