✅ FAST ➕ SIMPLE | MySQL Solution (Using CASE)
\nSELECT A.product_id, B.COLUMN_NAME as store,\nCASE\n    WHEN B.COLUMN_NAME = "store1" THEN store1\n    WHEN B.COLUMN_NAME = "store2" THEN store2\n    WHEN B.C
```\nSELECT A.product_id, B.COLUMN_NAME as store,\nCASE\n    WHEN B.COLUMN_NAME = "store1" THEN store1\n    WHEN B.COLUMN_NAME = "store2" THEN store2\n    WHEN B.COLUMN_NAME = "store3" THEN store3\nEND AS price\nFROM Products A, INFORMATION_SCHEMA.COLUMNS B\n  WHERE table_name = \'Products\' AND column_name != "product_id"\n  HAVING price IS NOT NULL\n```
['MySQL']