It depends on the individual dogs, but as far as breed description goes...
I would say from most snappy to least.
chihuahua
jack russell
bichon frise....well I might be bias, because i own one and he' the friendliet dog I ever own, most bichons I met also were very friendly...even when he goes crazy and has his bichon blitz, he would mouth, but NEVER ever bites, not even as much close his mouth a little bit, its always wide open...he doesn't even mouth much either.
He NEVER had an accident either. Except one time he had an upset tummy from something he ate, and of course he couldn't control that. But even when we got him, I was expecting some accidents since he was new to my house, but not even one.
I do believe to some extend breed descripitons are true, not in all cases though. In case of my doxie she's somewhat stubborn, was hard to housetrain, but she's now housetrained, and she did dig holes, but isn't notorious hole digger though. She fix the description of her breed to the ''T''.
Most chihuahuas...small breeds in general like poms, yorkies, ect are snappy and yappy...from what I seen and people say...but there are exceptions.
M rat terrier was snappy and yappy.