You'll probably want to move this over to the Teiid Designer discussions. From a Teiid 8+ perspective without Designer you'd probably be able to use textual DDL, which would be much easier to merge. Teiid Designer also offers metadata import/export via CSV files that may offer the ability to more easily perform an offline merge.
I thought UUID of an entity remained same once it is created as an identifier, so that the renames and updates can be done across the model. May be somebody can verify such assumption? Still IMO xmi files merging is pita, they are better suited for check-in/check-out model, not for concurrent modification.
Teiid Designer does not support merging XMI files at this time.
I'm not sure what/how you are trying to merge, but when a model is edited, object UUID's are not changed.
If you are copy/pasting Tables/columns, the PASTE action treats the "Clipboard" objects in a "structural" way but will not maintain the unique UUIDs. The pasted objects will be new objects with unique UUIDs.
We are trying to branch out the model and do development on it and once happy merge the model back to trunk. It is failing to do so cos svn can't merge the xmi.
MMUUID is the one that changes. I tried using the EMF Compare merge tool and it is failing to open the model because of the mmuuid.
Do you have any recommendation of how to achieve this?