How long do dogs remember?

My family had to give away my small west highland terrier about a year ago to some friends of ours. I haven't seen the dog since we gave him away but I'm going to their house soon to help them paint a room and move some stuff around. I've just been wondering how the dog will react, we had him for about 4 years and anytime I went away for even a few days..as a dog usually would behave, he'd go insane when he saw me again. I curious how he'll be around me after a whole year though. Has anyone experienced something like this?

i'm not too sure, but my uncles dog used to bite me playfully when he was a puppy, then when i next saw him 3 years later, he full on attacked my face (luckily moved and got a couple of scratches on nose and cheek, but took a nasty gash in the wrist when i covered my face)! i think he was trying to be playful again...i do actually love dogs though, so let us know how it goes will you?

He will know you and love you! Remember that scent is most important to dogs so he may not recognize you from a distance but once you're near he'll go bonkers.

Be sure to bring treats!

Dogs have poor short term memory. If they "get" something they tend to remember. Though Irish setters are the worst at this, failing to greet owners after a few month's separation. Poddles and terriers and some Lhasa Apso's are pretty good with memory.

A Westie will definitely remember you after a mere year.

I don't know bout dogs but I know cats have an excellent memory

Cats are not smart in the way dogs are smart. Cat fanciers sees all kinds of smart in them because they want to.

The only thing on a cat's mind when it is with people is: "if you were smaller, I could eat you."