I work full-time and Miles has been crated during the day from the second day I had him. It's a decent sized crate, so he can still move around. When I get home from work, we always go on a long walk and have some play time so he can get exercise and get some of that energy out! He sleeps in bed with me at night, so he's not crated then, either.
Crating him actually helped with potty training. He learned to hold it until I got home. Now that he's 8 months and doing well with potty training, I'm going to get a gate to keep him in the bathroom or kitchen. It's definitely possible to have a dog and work full-time. Just be sure that you're spending quality time with the dog when you're there.