oil pump, engine

the oil pump went out in my car, how bad could the engine be, like wat would typically happens to the engine if theres no pressure and it's running dry, I just want to know how extensive the damage is before I decide to have it rebuilt or w.e or be4 I replace the pump hoping the engine will still be runable. The car was only ran for like 30 seconds after the pump went out and the car turned off