I have a custom view (page) created using Views in Drupal 7.
It contains a taxonomy field and an (exposed) taxonomy filter. When viewing the custom page/view, it works exactly as needed and a user can select a taxonomy filter to limit results accordingly. For example, the default view is /books and the user, via the exposed filter can select /books?book_type=21 to show only the books that have taxonomy ID 21.
The problem I am experiencing is that I need a second custom view (essentially a series of thumbnails, each depicting a different 'book_type') to link directly to the /books?book_type=21 URL path. Within this second view, I have added the appropriate taxonomy field and via the Rewrite Results option of the field, I have selected Output This Field as a Link and inserted books?book_type=[field_book_taxonomy], where [field_book_taxonomy] is the referenced taxonomy field.
When I view this thumbnail page, the link works, but the URL contains the taxonomy name rather than ID. So whilst I need /books?book_type=21, the page receives /books?book_type=ficton.
I have tried various Contextual Filters, including Term Name converted to ID, but the URL always passes name and the page therefore returns "An illegal choice has been detected".
Ideally I would like to retain the path /books?book_type=ficton on the initial view and have this interpreted successfully by the actual filtered view.
Please can someone offer a pointer as to where I am going wrong with this?