Depends on the time of year and the chickens.
For my main coop, I used to have water inside and out. Food is inside only. But I notice they don't drink the water inside, but kick shavings in it constantly. (even with it elevated) So I spend more time cleaning it and they don't drink out of it. Now if I had a broody, there would be water in there. So this time of year, no water inside, but I have an automatic door that opens before they are even off the roost. So I don't have to worry about them being without water. But in the winter, I do put water inside as it doesn't freeze as much and they spend more time inside then. Then I take the outside waterer inside my house for the night and put it back out in the morning to keep it from freezing.
Now for my small coop, I have water inside. (food too) I try putting water outside for them, but the crazy birds almost always knock it over.