Re: [emf-dev] Handling Referential Integrity

[Ed Merks <merks@xxxxxxxxxx>]

Ashely,

My standard answer to questions on the
mailing list is to please ask the questions in the newsgroup instead.

Bugzilla https://bugs.eclipse.org/bugs/show_bug.cgi?id=61639
tracks this issue.  We do plan to fix it but just haven't had the
time.

The way we plan to go about solving
this is to use EcoreUtil.UsageCrossReferencer to find all uses of the deleted
object and then to create commands to remove those uses too.


Ed Merks/Toronto/IBM@IBMCA
mailto: merks@xxxxxxxxxx
905-413-3265  (t/l 969)

"Ashley at Metamaxim" <ashley.mcneile@xxxxxxxxxxxxx>
Sent by: emf-dev-admin@xxxxxxxxxxx

09/16/2004 03:40 PM

Please respond to
emf-dev

To	<emf-dev@xxxxxxxxxxx>
cc
Subject	[emf-dev] Handling Referential Integrity

Hi
 
I am a new user of EMF, and am looking for
information concerning handling referential integrity in EMF (specifically,
in the editor that EMF generates for a model).
 
In April of this year, there was a posting
to [news.eclipse.tools.emf] by Sugato Bagchi on this subject.
 
Ed Merks replied to Sugato with:
 
> The model knows nothing about delete;
it's not a model concept.  In the editor,
> when you do delete, it just removes the object from its container
making it
> unreachable.  It would be very nice for the framework to handle
> cleanup-all-references on delete automatically, wouldn't it?  Feel
free to open
> a bugzilla feature request and we'll look into it (but it will take
us quite
> some time probably).
 
In the application I am building with EMF,
this lack of referential integrity is a problem. At present, if you delete
an object in the generated editor, references to it remain intact. However
if you then save and reload the model, the references disappear. I don't
think that save and reload should cause this kind of change to the state
of the model. What I need is for the references to be cleaned up at the
time of the delete.
 
I have looked in the EMF bug/desired feature
list, but this does not seem to registered as either a bug or a feature
request. But maybe it is there, and I just did not look in the right place!
What I need to know is:
 
1. Has this been registered as an issue,
and are there any plans to fix it?
 
2. If not, where can I get an example of
the code I would need to write to handle referential integrity myself?
 
With thanks
Ashley
 
Ashley McNeile
Metamaxim Ltd.
email: ashley.mcneile@xxxxxxxxxxxxx
web: www.metamaxim.com