I'm trying to find a way to look up the relationship IDs from ArcGIS Server programmatically using the layer IDs (integers) from ArcGIS Server, which we manage manually in our map document. I'm sure there is a way to do it through the REST API, but I was hoping there might be a way to do it through the map object, possibly with the layer IDs used by the map (strings). Our layer names are deliberately simple and unlikely to change.
In the documentation for feature layers, I can see the properties for relationships that would get me what I want, but I am having a hard time finding any documentation on tables. The map object has a property called tables, but I don't see anything that is formally documented on tables. If you have any ideas on how to avoid changing relationship IDs or on how to access tables in the map, that would be appreciated.