Self Explanatory && Simple
\r\n\r\n# Code\r\n\r\n# Write your MySQL query statement below\r\nSELECT product_id, \r\n\'store1\' AS store, \r\nstore1 AS price \r\nFROM products\r\nWHERE sto
\r\n\r\n# Code\r\n```\r\n# Write your MySQL query statement below\r\nSELECT product_id, \r\n\'store1\' AS store, \r\nstore1 AS price \r\nFROM products\r\nWHERE store1 \r\nIS NOT NULL\r\nUNION\r\nSELECT product_id, \r\n\'store2\' AS store,\r\nstore2 AS price\r\nFROM products\r\nWHERE store2\r\nIS NOT NULL\r\nUNION \r\nSELECT product_id,\r\n\'store3\' AS store,\r\nstore3 AS price\r\nFROM products\r\nWHERE store3\r\nIS NOT NULL\r\n\r\n```
['Union Find', 'MySQL']