The smart restaurateur additionally has the staff place any open bottles used for by-the-glass pours, both white and red, in the refrigerator to retard oxygenation even further. High-end restaurants may sometimes even pour out any wine remaining in those open bottles or send them to the kitchen refrigerator for cooking use every night at closing.
At home, if you have any wine left over in a bottle, the best preservation is to re-cork or cap the bottle tightly and put it in the refrigerator or even the freezer to slow down spoilage. In the refrigerator, both reds and whites will have minimal taste changes for 3-4 days, and in the freezer even longer. The only downside is to remember to take out the bottles for enough time before consuming the wine so that the temperature comes back to serving recommendations.
In a restaurant, it is usually impractical to wait for a refrigerated red wine come back to serving temperature before serving to a guest, but white wines that are open can always be refrigerated all of the time after opening and may last for 2-3 days.