Wotae: 01.08.2018
TIP: I always bought daily necessities at Mercadona because I believe they have the best selection and the most affordable prices. Aldi seemed very expensive to me and the SPAR markets are more like 7/11 in America - meaning, you can get a soda. Instead, I would recommend getting barbecue meat at Hiper Centro, as they usually have a fresh meat counter with their own butchers.
The opening hours are usually from Mon-Sat 09:00/09:30h - 21:00/22:00h and Sundays usually until 14:00h. If you forget something, you can always find opportunities to shop almost anytime.