How do you remove white rings from wooden coffee tables?

An "Old Home Remedy" works really well for me....just take real mayonaise and rub it on the spot...then let it set with a little "glob" covering it, overnight. Next day, wipe off, give a good rubbing in....and the spot should be gone. If it is still faintly visible...then take a very fine grade of sand paper, rub the area to blend in / erase the spot / ring...then, here's another old "decorator's / designer's tip / secret: then take dark brown or cordovan red shoe shine CAKE / WAX in the tin....whichever color most closely matches the tone of the wood...then rub it in to completely fill out the slightly sanded area & the ring! it should look almost new! Little do most people know that shoe wax is the best furniture scratch & blemish repairer / restorer...it works miracles! This has saved me many a refinishing job on a piece of furniture! Best of Luck!