Support for non-standard columns

[dmbreakey]

Support for non-standard columns in the Calibre database would be very useful.

My Calibre database is heavily customized, with a large number of custom columns, such as "Characters", "Collection", "Editor" (plus a whole bunch of comics-related fields, such as Colorist, Inker, Penciller, etc), as well as "Locations" and others.

While I see that the UI does already recognize new columns and reports them in the book detail view, the ability to click directly on one of these, just like the "Tags" field, and get a result set comprising of those books matching that term, would be very useful to me.

I'm not aware of any alternatives, and apologies if I've missed that this request has already been submitted; I didn't see anything that appeared relevant when I searched, but I only reviewed under "Enhancements".

My thought would be to enhance the configuration UI to allow the admin to select which additional Columns should be considered for this, rather than simply detecting and processing all discovered columns automatically, as I assume there is additional overhead and caching involved. However, I haven't actually reviewed code yet.

I would be happy to take a crack at this myself, except my experience with this kind of Python (and esp. JavaScript) is minimal. Still I might review and see if I can.