What do you mean by "very long"? If she needs to go out every hour or more, she might have a UTI, so I'd schedule a vet check.
As for wanting your dog to signal when she needs to go . . . I've found that some dogs signal and some don't. My friend's dog will go and stand by the door, but my older dog doesn't. He will respond if I ask "Do you need to go outside?" If he does, he runs to me.
I'm not sure if eight hours is always a realistic expectation. Cupid can hold it overnight, and he sometimes holds it while I'm at work (although I have pee pads available just in case). But otherwise, he goes every three or four hours. That's just my experience--others might have other opinions.
As for wanting your dog to signal when she needs to go . . . I've found that some dogs signal and some don't. My friend's dog will go and stand by the door, but my older dog doesn't. He will respond if I ask "Do you need to go outside?" If he does, he runs to me.
I'm not sure if eight hours is always a realistic expectation. Cupid can hold it overnight, and he sometimes holds it while I'm at work (although I have pee pads available just in case). But otherwise, he goes every three or four hours. That's just my experience--others might have other opinions.