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?

Also, be careful with Oracle and cross-schema joins. There can be huge 
performance differences depending on how the database is configured, especially 
if the schemas are on different physical/virtual servers.

If you can't make the actual modeled relationship work, you can always 
approximate it by writing cover methods that do the same work that the normal 
getters and setters would, but do it with fetches instead. Modeling it is 
certainly the easiest way to go, but in the situation of 
cross-schema/cross-database stuff, you are walking in a mine field.

Dave
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