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Re: Inverse to-one relationships
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Re: Inverse to-one relationships


  • Subject: Re: Inverse to-one relationships
  • From: Paul Hoadley <email@hidden>
  • Date: Fri, 23 Jul 2010 08:09:17 +0930

On 23/07/2010, at 7:42 AM, Chuck Hill wrote:

>>> How are you modeling these relationships?
>>
>> Originally, just this: a mandatory, to-one relationship from A to B.  Consider it to be a parent (B) with optional child (A).  Every child has a parent (hence the current mandatory to-one from A to B), and every parent has zero or one child.  So I've tacked on an optional to-one relationship from B to A to model the latter.  I take it there's no way to convince EOF that these relationships are inverses, and get the convenience of updating both sides of the relationship at the same time.
>
> Where are the FKs?  B hold's A's PK as an FK?

Yes, and vice versa.  Only difference is that B to A is optional (parent can have zero children), A to B is mandatory (child must have a parent).

> They both have the same PK?

No.  (Would this help?)


--
Paul.

http://logicsquad.net/


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References: 
 >Inverse to-one relationships (From: Paul Hoadley <email@hidden>)
 >Re: Inverse to-one relationships (From: Chuck Hill <email@hidden>)
 >Re: Inverse to-one relationships (From: Paul Hoadley <email@hidden>)
 >Re: Inverse to-one relationships (From: Chuck Hill <email@hidden>)

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