링크

방식 1

-- 코드를 입력하세요
SELECT WAREHOUSE_ID, WAREHOUSE_NAME, ADDRESS, 
	coalesce(FREEZER_YN,'N') AS FREEZER_YN 
FROM FOOD_WAREHOUSE 
WHERE WAREHOUSE_NAME LIKE "%경기%"
ORDER BY WAREHOUSE_ID 

방식 2

SELECT WAREHOUSE_ID, WAREHOUSE_NAME, ADDRESS, 
    CASE WHEN FREEZER_YN IS NULL THEN "N"
    ELSE FREEZER_YN
    END AS FREEZER_YN
FROM FOOD_WAREHOUSE 
WHERE ADDRESS LIKE '경기도%'
ORDER BY WAREHOUSE_ID;