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-- GROUP BY 방법
SELECT CART_ID
    FROM (
        SELECT DISTINCT CART_ID, NAME
            FROM CART_PRODUCTS
            WHERE NAME IN ('Milk', 'Yogurt')
        ) T1
    GROUP BY CART_ID
    HAVING COUNT(1) >= 2
    ORDER BY CART_ID
    
-- SUBQUERY 방법
SELECT DISTINCT CART_ID
    FROM CART_PRODUCTS
    WHERE NAME IN ('Milk')
        AND CART_ID IN (SELECT CART_ID 
                            FROM CART_PRODUCTS
                            WHERE NAME IN ('Yogurt'))

SELECT ANIMAL_ID
    , NAME  
    , SEX_UPON_INTAKE
    
    FROM ANIMAL_INS
    WHERE NAME REGEXP "^(Lucy|Ella|Pickle|Rogan|Sabrina|Mitty)$"
    ORDER BY ANIMAL_ID

SELECT T1.ANIMAL_ID
    , T1.NAME
    FROM ANIMAL_OUTS T1
        LEFT JOIN ANIMAL_INS T2
            ON T1.ANIMAL_ID = T2.ANIMAL_ID
                AND T1.ANIMAL_TYPE = T2.ANIMAL_TYPE
    WHERE T2.ANIMAL_ID IS NULL