They are XML, but it seems that they seem to be recreated each time the map is being saved and the ids of the elements inside are changing each time. The tool (Message Designer) is quite old and not very convinient to use.
Have you any hints how to version, track changes in such map? Or is there an alternative for Message Designer?
When developing and loading Oracle XML Gateway message maps, there are several methods you can employ to track versions. However, they are all manual and require setting a standard within a development team.
Aside from version tracking tools like SVN etc. each time you change a message map, you can change the Map name in the Properties tab. Then each time you load the map, you will be able to choose which version you want to use/test from the Trading Partner Setup in the XML Gateway. If your question is how to compare two existing map files to find the differences between them... unfortunately, the most effective way is to start two sessions of Message Designer, tile them and move through them side by side. Identifying which elements are mapped to which is relatively straightforward (assuming you are comparing slight variations of the same source and target definitions and mapping). You can focus particularly on elements or levels that have a blue circle icon in the Element Mapping tab - that's where the logic used becomes important. True that the map files themselves are in XML, but it is of little use to compare the XML one to the other using a comparison tool... there's really no substitute in this instance for human analysis. Using the Message Designer tool to compare exposes the logic and the pre, in, and post process procedures as well as the elements themselves.
Hope this helps, if I have misunderstood the question please feel free to elaborate and I'll be happy to answer again.
Best,
Meg Hanson