Error with table with a key in navigation property

[VanessaSap]

Hello,

When I try to implement Change Tracking on a table where the key is a navigation property, I get the following error:

"Error: CDS compilation failed (@sap/cds-compiler v5.4.0) srv/admin-service.cds:408:45: Error: Unexpected usage of structured type “to_Rule” (in entity:“RulesDerivation”/column:“changes”/on)"

entity RuleDerivation : managed { key to_Rule : Association to design.Rule ... }

Could you help me understand if there’s a way to work around this problem?

[VanessaSap]

Let me know if you need more details

[jbm1991]

Did you find any solution to this problem as I've just run into exactly the same thing? Some further details for reproduction:

//schema.cds
namespace my.bookshop;

entity Books {
  key ID      : Integer;
      title   : String;
      stock   : Integer;
      authors : Association to one Authors;
      pages   : Association to many Pages
                  on pages.book = $self;
}

entity Authors {
  key ID    : Integer;
      name  : String;
      books : Association to many Books
                on books.authors = $self;
}

entity Pages {
  key book : Association to one Books;
  key num  : Integer;
      text : String;
}

// cat-services.cds
using my.bookshop as my from '../db/schema';

service CatalogService {
    @readonly
    entity Books   as projection on my.Books;

    @readonly
    entity Authors as projection on my.Authors;

    @readonly
    entity Pages   as projection on my.Pages;
}

// change-tracking.cds
using {CatalogService} from './cat-service';

annotate CatalogService.Books {
    stock @changelog;
    title @changelog;
}

annotate CatalogService.Authors {
    name @changelog;
}

annotate CatalogService.Pages {
    num  @changelog;
    text @changelog;
}

[nkaputnik]

Hello, NON-UUID keys and multiple keys have been a known limitation of Change-Tracking in the past. We have a current branch in development to fix this issue for the next release. I'm not sure whether this will completely fix associations as keys in the first run. In the meanwhile, the only workaround would be to use the association as a surrogate key, and have a single "real" key. The next release should fix this.

Best, Nick

[VanessaSap]

Did you find any solution to this problem as I've just run into exactly the same thing? Some further details for reproduction:

//schema.cds
namespace my.bookshop;

entity Books {
  key ID      : Integer;
      title   : String;
      stock   : Integer;
      authors : Association to one Authors;
      pages   : Association to many Pages
                  on pages.book = $self;
}

entity Authors {
  key ID    : Integer;
      name  : String;
      books : Association to many Books
                on books.authors = $self;
}

entity Pages {
  key book : Association to one Books;
  key num  : Integer;
      text : String;
}

// cat-services.cds
using my.bookshop as my from '../db/schema';

service CatalogService {
    @readonly
    entity Books   as projection on my.Books;

    @readonly
    entity Authors as projection on my.Authors;

    @readonly
    entity Pages   as projection on my.Pages;
}

// change-tracking.cds
using {CatalogService} from './cat-service';

annotate CatalogService.Books {
    stock @changelog;
    title @changelog;
}

annotate CatalogService.Authors {
    name @changelog;
}

annotate CatalogService.Pages {
    num  @changelog;
    text @changelog;
}

Hello, Unfortunately, I had to make a structural change to implement this history.

[nkaputnik]

Please see also here: https://github.com/cap-js/change-tracking/issues/130