SQL 기본 및 활용

STANDARD JOIN!!

INNER JOIN

NATURAL JOIN

-> USING ON WHERE 절에 JOIN 조건을 정의 할수가 없음

EX)

ON JOIN

SELECT TEAM_NAME, TEAM.STADIUM_ID, STADIUM_NAME

FROM TEAM JOIN STADIUM

ON TEAM.STADIUM_ID = STADIUM.STADIUM_ID;

USING JOIN

SELECT TEAM_NAME, TEAM.STADIUM_ID, STADIUM_NAME

FROM TEAM JOIN STADIUM

ON STADIUM_ID ;

WHERE JOIN

SELECT TEAM_NAME, TEAM.STADIUM_ID, STADIUM_NAME

FROM TEAM , STADIUM

WHERE TEAM.STADIUM_ID = STADIUM.STADIUM_ID ;

EX)    팀과 스타디움 테이블의 팀ID로 JOIN 함. 단 스타디움 테이블의 팀ID 는 HOMETEAM_ID로 되있음

ON JOIN 조건

SELECT TEAM_NAME, TEAM_ID, STADIUM_NAME

FROM TEAM JOIN STADIUM

ON TEAM.TEAM_ID = STADIUM.HOMETEAM_ID;

WHERE 절 JOIN 조건

SELECT TEAM_NAME, TEAM_ID, STADIUM_NAME

FROM TEAM, STADIUM

WHERE TEAM.TEAM_ID = STADIUM.HOMEtEAM_ID;

ON 다중 조인

CROSS JOIN

UNION 

UNION ALL

출처 : The Guide for SQL Professional Sql 전문가 가이드 2013 Edition