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Re: Many-To-Many Relationship across DB with different users
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Re: Many-To-Many Relationship across DB with different users


  • Subject: Re: Many-To-Many Relationship across DB with different users
  • From: Ramsey Gurley <email@hidden>
  • Date: Wed, 14 Mar 2012 08:47:42 -0700

On Mar 13, 2012, at 10:08 PM, David Avendasora wrote:

>
> On Mar 13, 2012, at 8:13 AM, Chuck Hill wrote:
>
>> It looks like the problem is the join table.  Where does that sit?  I suspect that Propogate Primary Key is not going to work across databases. You might have to manage that manually.
>>
>> Chuck
>
> Is this where I put my rant about the evils of join tables with compound PKs? Because it sure seems like it…
>
> Seriously though, Troy, I think this is a situation where you might be better off making the join table between Student and Teacher an actual Entity with a simple PK and separate FKs for Student and Teacher and get rid of propagate primary key. You can still flatten relationships for reading values, but EOF won't automatically create the record in the join table, but how hard is that to do anyway?

I was reading about graph databases recently. They look to be designed explicitly to solve the problems you've described in previous emails about many-to-many relationships.  Just thought I'd throw that out there :-)

Ramsey


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  • Follow-Ups:
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References: 
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 >Many-To-Many Relationship across DB (From: Troy Lumasag <email@hidden>)
 >Re: Many-To-Many Relationship across DB with different users (From: David Avendasora <email@hidden>)

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