GROUP BY
특정 칼럼을 기준으로 데이터를 그룹핑함
문법
1 | SELECT * FROM 테이블명 GROUP BY 그룹핑 할 기준 칼럼명 |
예제
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | DROP TABLE IF EXISTS `student`;CREATE TABLE `student` ( `id` tinyint(4) NOT NULL, `name` char(4) NOT NULL, `sex` enum('남자','여자') NOT NULL, `address` varchar(50) NOT NULL, `distance` INT NOT NULL, `birthday` datetime NOT NULL, PRIMARY KEY (`id`)) ENGINE=InnoDB DEFAULT CHARSET=utf8;INSERT INTO `student` VALUES (2, '박재숙', '남자', '서울', 10, '1985-10-26 00:00:00');INSERT INTO `student` VALUES (1, '이숙경', '여자', '청주', 200, '1982-11-16 00:00:00');INSERT INTO `student` VALUES (3, '백태호', '남자', '경주', 350, '1989-2-10 00:00:00');INSERT INTO `student` VALUES (4, '김경훈', '남자', '제천', 190, '1979-11-4 00:00:00');INSERT INTO `student` VALUES (8, '김정인', '남자', '대전', 200, '1990-10-1 00:00:00');INSERT INTO `student` VALUES (6, '김경진', '여자', '제주', 400, '1985-1-1 00:00:00');INSERT INTO `student` VALUES (7, '박경호', '남자', '영동', 310, '1981-2-3 00:00:00'); |
1 | select sex from student group by sex; |
1 | select sex,sum(distance), avg(distance) from student group by sex; |
