As per my understanding, you want to export or show the VQL of an interface and its implementation.
For exporting the VQL if you are using the VDP Admin Tool you can right click on the interface and click on Export. I’ve tried this approach and I get a file with the VQL of the interface and the implementation.
To see VQL of the interface. I‘d click on the interface and at the left top you can see three tabs. There is a tab which its name is VQL and if you click on it, it will display the VQL code of the interface.
I find it very useful to review [the VDP VQL Guide](https://community.denodo.com/docs/html/browse/8.0/en/vdp/vql/index) for getting more information on the VQL syntax.. For this scenario, you can refer to [Defining an Interface View](https://community.denodo.com/docs/html/browse/8.0/en/vdp/vql/defining_a_derived_view/defining_an_interface_view/defining_an_interface_view) section of the VDP VQL Guide.
Hope this helps!