In case if two or more columns have equal value which one is chosen by greatest function?
SELECT a.*,
greatest(
coalesce(addon, cms, upoint,card*8000),
coalesce(cms, upoint,card*8000,addon),
coalesce(upoint, card*8000,addon, cms),
coalesce(card*8000, addon, cms,upoint)
) new_high_col
from tserenlkham.data_shift_202001_a4 a