Battery removal of 2003 buick regal?

if i remove my battery to put a new one in/ or charge the old one will all my stuff like mileage and stuff like that be lost? i would just charge it with the battery still in the car but dont have acess to a outlet anywhere near my place. soi would have to take the battery inside my place to charge it. so my question is if i remove the battery will i lose all my mileage and be royaly screwed?