Does attach lens to dslr all the time good for maintain the camera?

Does attach lens to dslr all the time good for maintain the camera? - 1

Added (1). I have nikon d5300 and i only have 18-55mm lens. So i'm considering to attach it to the camera all the time

There's no problem leaving the lens attached to the body. When they are unattached, make sure to use the lens covers and the body cap to keep dust from getting on the lens and the sensor.

Ideally, you'll want to keep your lens in a dry cool area
If you live in a place with either of those conditions, then you will be fine keeping your lens on your DSLR
If you live in a hot humid area, then there's a slight risk of fungus growth on the lens which ruins the lens.

If you have no other lens, keep it that way, lens attached to the camera even during storage.

Yes you should keep it attached, unless you are changing lenses. Removing it increases the chance of dust etc getting on the sensor.

That's a good practice. It's what most people do. Those who don't will use the body cap that came with the camera. I would recommend leaving the lens on the camera all of the time to prevent dust from entering the camera and eventually getting onto your sensor.

If you live in a place with either of those conditions, then you will be fine keeping your lens on your DSLR

12 POINTERS THAT WILL Help YOUR DSLR LIVE LONGER http://www.diyphotography.net/how-make-your-dslr-last-longer/