Women with weaves--how do they/you deal with washing hair?

Presumably when you get a weave, you just leave it in for…well, a while, and it’s sewn in. So can you wash it? Googling says there are ways of doing it but I’m a bit skeptical that it’s really as good as…well, just washing your hair the normal way. My hair gets oily pretty fast so the idea of just having something sitting on my hair as it gets greasy/oily freaks me out…

Surely you’ve read the “no 'poo” threads. Hair tends to balance itself out if given the chance.

For people whose hair doesn’t deal with “no poo,” though? My hair just doesn’t balance. It gets oilier and more disgusting with time.