I have a 10 year old Cavalier King Charles Spaniel boy and a 7-8 month old black American Shorthair girl.
My cavvie (Excalibur) is, in general, pretty leery of cats. He doesn't interact with her on purpose very much. He doesn't antagonize her or really do anything other than give her a cursory sniff if she walks near him. The only real interaction he does is if she's hassling him while he eats. He usually whips around and barks right in her face, which makes her back off. Usually two or three times and he'll have a peaceful meal. He doesn't mind if she lies next to or on him. Cavaliers (from my experience anyway) aren't really into "predator/prey" games - they're all about cuddle play.
My cat, Sombra, is young and is a bit of a savage sometimes. She's very inquisitive and is into everything at all times. She has toys, her own food and water, a private litterbox, a scratching post and lots of safe places she can lurk. She gets fed regularly, and despite eating like a horse, she's pretty waifish. Probably because she's an absolutely maniac anytime she's awake.
She bites and scratches, which gets her a spray from the compressed air can. She's learned over time not to get on the countertop in the kitchen from this. The biting and scratching isn't really stopping, and now she's taken to jumping on my dog's back and sinking her teeth into the back of his neck. My dog's kind of old, so he doesn't have the agility required to shake her off so he just yells out while she bites him.
I can't always be there to separate and spray. I love both my pets, but my partner and I agree that Sombra is 100% the instigator of their squabbles. Is there anything else we can be doing to help her learn that this is a no-bite-no-scratch household?