How to remove water ring from black painted table?

My lovely daughter left a cup on her nightstand and it left a white water ring. It is painted black. Not sure what to use. Have tried polishing with furniture polish but no help.How to remove water ring from black painted table?
SS,the only way to resolve this is try a polishing compound with very minuet,or fine abrasive in it,after doing that you will need to use a good wax if its painted with enamel paint you can use regular car wax,and bring the gloss back to the tableHow to remove water ring from black painted table?
I would scrap the paint away around the ring, then paint it black again. If you really want to go out of your way about the right shade of black go to a paint store to have them match the shade. trust me i'm going into landscape and home design.
Go to Home Depot or Lowe's and get some ';pumish';. Polish with this and the ring will begone. Suggest you might want to get a piece of glass cut while at the store to use as a protector for the painted surface.