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Re: Multi tables having a to-many relationship to the same table
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Re: Multi tables having a to-many relationship to the same table


  • Subject: Re: Multi tables having a to-many relationship to the same table
  • From: Paul Lynch <email@hidden>
  • Date: Thu, 27 Apr 2006 18:20:15 +0100


On 27 Apr 2006, at 17:47, Chuck Hill wrote:

That does not make any sense in OO or RDBMS terms. Your database will not allow you to have a FK to two different tables. In OO, you would not want a relationship to two different classes not in an inheritance hierarchy. At the very least your code would be littered with casts and instanceof tests. Ugly.

As a interesting point of fact, I have a customer with a legacy database that does exactly this, so it is possible. Just because it is ugly (and yes, it is) and doesn't make any sense, doesn't mean that a customer won't do it.


But please, don't!

Paul
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  • Follow-Ups:
    • Re: Multi tables having a to-many relationship to the same table
      • From: Chuck Hill <email@hidden>
References: 
 >Multi tables having a to-many relationship to the same table (From: "Rohrbaugh, John H" <email@hidden>)
 >Re: Multi tables having a to-many relationship to the same table (From: Chuck Hill <email@hidden>)

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