Sortable admin columns, when data isn't coming from post_meta

Question

I have a custom post type that uses a custom taxonomy. I'm imposing a limit of a single term to each post (using a custom meta box drop down on the edit post screen for the CPT). The term for the taxonomy is assigned using the standard wp_set_object_terms() function. How can I make the taxonomy column sortable (using WP 3.1rc3)?

This post by Scribu got me almost there.

However, since I'm not using a numeric value stored in a meta key, the {name}_column_orderby function will not work for me.

How can I create sortable columns within the manage-edit screens, when the information that I'm listing does not come from the post_meta table?

Answer 1

See the follow-up post: http://scribu.net/wordpress/sortable-taxonomy-columns.html