Solution with UNPIVOT and UNION , UNPIVOT IS BIT FASTER
UNPIVOT IS ONLY AVALIBLE IN MY SQL\n\nSELECT Product_id, Store, Price\nFrom Products\nUNPIVOT\n(\nStore for price in (\n[store1],[store2],[store3]\n)\n) as u\n\
UNPIVOT IS ONLY AVALIBLE IN MY SQL\n```\nSELECT Product_id, Store, Price\nFrom Products\nUNPIVOT\n(\nStore for price in (\n[store1],[store2],[store3]\n)\n) as u\n```\nThis Query We Can run Everywhere \n```\nSelect Product_id, \'store1\' as Store, Store1 as Price\nfrom Products\nwhere store1 IS NOT NULL\nUNION\nSelect Product_id, \'store2\' as Store, Store2 as Price\nfrom Products\nwhere store2 IS NOT NULL \nUNION\nSelect Product_id, \'store3\' as Store, Store3 as Price\nfrom Products\nwhere store3 IS NOT NULL \n```\nHappy Learning
['MySQL']