Ragu recipe ideas for Gnocchi al Cinghiale holiday meal

Every year we change up our Christmas feast and make something we've never had before. This year my husband found this description for an Italian dish: Gnocchi al Cinghiale
Fresh house-made potato gnocchi with slowly braised wild boar and a sweet and sour tomato ragu.

I'm sure I can find loads of gnocchi recipes to work with, and I've got the wild boar on order. What I'm wondering is what "sweet and sour tomato ragu" means in this context? I know the basic concept is flavorful things that you braise the meat low and slow in, pull the meat, shred a bit, strain the ragu, then serve them together with the (in this case) gnocchi.

It's the "sweet and sour" idea I'm not sure how to search for, exactly. Anyone have ideas what they mean by that? My husband did find this one: http://www.foodnetwork.com/recipes/ra..., but that seems to fail on the "sweet and sour" idea. I am also not especially -married- to the idea of sweet and sour as described above. My husband tends to prefer spicy to sweet sauces.

Just looking for input/thoughts for either the ragu or the gnocchi. :) We do prefer fluffy gnocchi to the denser ones. :) Ideas for preferred recipes on that front would be nice, too. :)

Thanks everyone! :)