docs: Add a ref for the 'overloaded' SDL keyword
@@ -33,6 +33,11 @@ Declare a *concrete* link "friends" within a "User" type:
index on (__subject__.name);
}
+.. _ref_eql_sdl_links_overloading:
+
+Overloading
+~~~~~~~~~~~
+
Any time that the SDL declaration refers to an inherited link that is
being overloaded (by adding more constraints or changing the target
type, for example), the ``overloaded`` keyword must be used. This is
