Hello there,
I want to add a relation between AOP_Case_Updates and Cases models so I can take the date saved in AOP_Case_Updates table and print it in a PDF template related to the Cases model
thank you
Case updates are a peculiar module, not everything is possible (or straight-forward) with them.
Sometimes there are other ways to approach. A typical one would be a Workflow (or an after_save logic hook) that copies that date into the Cases module, into a custom field, so that it is readily available on the Template.