Hey, I have bought new guns and understand wanting to carry them when hunting. There is nothing wrong with that. Properly used, at close ranges with good shot placement a 9mm is a good hunting round for game up to deer sizes; however I would consider it too small for hogs in anything but a back up or a last ditch weapon scenario.
Supposing hog zilla charged you and you unloaded with a 9mm, you might take him out, you might not, but what else could you do? Chances are there isn't a lot short of a well placed rifle round that would have done dropped him.
Say that you go into the brush after a hog that you wounded earlier, I would take the sidearm, as rifles are unwieldy in brush. The 9mm would prove more effective there, but you need to keep shots around the head, neck and ear areas. Hit the spinal column or brain and it is over. Study hog anatomy.
I always carry a sidearm when hunting, for 1 it is fun. 2, you never know who you might run into. I think we can all remember that loony toon in Wisonson who just shot the crap out of some hunters. With more and more illegals and convicts and nut cases out in the world growing drugs, or kidnapping or murdering in wilderness areas, it pays to be careful. But the most imporant thing is the keep your first shot well placed (the original rifle shot) and all the other conversation is moot eh?
Good luck.
For the record the .357 is a much better hunting round, but the 9mm is acceptable if you want to carry it.