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Re: Foreign key problem

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Tue, 13 Jun 2006 23:44:16 +0200
Message-ID: <448f317f$0$31645$e4fe514c@news.xs4all.nl>


Kenneth Downs wrote:

> mAsterdam wrote:
>>

>>>In the limited example given in the post, yes.
>>>
>>>In fact we have half-dozen or so other flags on the FK table, two of
>>>which combine to provide multiple FK's between any two tables.
>>>We employ a "suffix" and a "prefix" property, each of which is used
>>>to alter the names of the columns in the child tables by adding
>>>the obvious prefix or suffix to each column in the child table.

Yes, that is clear. What your example also showed is that what you consider the /obvious/ pre- or suffix may be borrowed from the place in the model rather than from the place in the universe of discourse (UOD).

Say we have a database with games of bridge:

   Player(*Id, Ranking, ...
   Game(*G#, N_player, E_player, S_player, W_player, ...

Here are four FK's in the same 'child' table referencing the very same 'parent' table (adopting your terminology for now). Terms from the place in the model (_parent, _child) do not help at all to distinguish the FK's.
Terms from the place in UOD, specifically the /role/ of the Player in the Game, do help: North, East, etc.

[snip] Received on Tue Jun 13 2006 - 16:44:16 CDT

Original text of this message

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