SELECT U.USER_ID,
    U.NICKNAME,
    CONCAT(U.CITY, ' ', U.STREET_ADDRESS1, ' ', U.STREET_ADDRESS2) AS 전체주소,
    CONCAT(SUBSTRING(U.TLNO, 1, 3), '-', SUBSTRING(U.TLNO, 4, 4), '-', SUBSTRING(U.TLNO, 8)) AS 전화번호
FROM USED_GOODS_USER as U
INNER JOIN USED_GOODS_BOARD B ON U.USER_ID = B.WRITER_ID
GROUP BY 1
HAVING COUNT(B.WRITER_ID) >= 3
ORDER BY 1 DESC
출처: <https://ittrue.tistory.com/412> [IT is True:티스토리]