[프로그래머스 ORACLE SQL]조건에 맞는 사용자 정보 조회하기★SUBSTR()★한국말 열 쓸때 그냥 작은따옴표 붙이지 않기

조건에 맞는 사용자 정보 조회하기

https://school.programmers.co.kr/learn/courses/30/lessons/164670

프로그래머스

SELECT B.USER_ID , B.NICKNAME ,B.ADDRESS AS 전체주소 ,B.TLNO AS 전화번호  FROM
(SELECT WRITER_ID ,  COUNT(WRITER_ID) FROM USED_GOODS_BOARD
GROUP BY WRITER_ID
HAVING COUNT(WRITER_ID)>=3) A LEFT JOIN 
(SELECT USER_ID , NICKNAME , CITY ||' '|| STREET_ADDRESS1 || ' '|| STREET_ADDRESS2 AS ADDRESS, SUBSTR(TLNO,0,3)||'-'||SUBSTR(TLNO,4,4)||'-'||SUBSTR(TLNO,8,4)  AS TLNO  FROM USED_GOODS_USER) B
ON A.WRITER_ID = B.USER_ID
ORDER BY B.USER_ID DESC

==> SUBSTR(열 , 시작번호, 끝번호)