To be clearer, if i right click on on a database field i don't want to see the "Properties" item:

If i right click on a variable field i want to see the "Properties" item:

(I am talking about the "Properties" item as an example, but i need to do this on other items).
Alternatively, to me would be ok to completely disable the "Data sources" context menu and leave the "Variables" context menu.
Thanks.