mysql每日一题0721 关联查询
😄题目如下
测试数据
CREATE TABLE T0721
(
DOCNUM INT,
STATUS VARCHAR(26)
);
INSERT INTO T0721 VALUES (33,'FULL');
INSERT INTO T0721 VALUES (33,'NOFULL');
INSERT INTO T0721 VALUES (34,'FULL');
INSERT INTO T0721 VALUES (35,'FULL');
INSERT INTO T0721 VALUES (35,'NOFULL');
INSERT INTO T0721 VALUES (36,'FULL');
INSERT INTO T0721 VALUES (37,'FULL');
INSERT INTO T0721 VALUES (38,'FULL');
INSERT INTO T0721 VALUES (38,'NOFULL')
参考答案
- solution1
SELECT
a.docnum
FROM
t0721 a
LEFT JOIN ( SELECT docnum, count( DISTINCT STATUS ) status_num FROM t0721 GROUP BY 1 ) b
ON a.DOCNUM = b.docnum
WHERE
status_num = 1
AND a.STATUS IN ('FULL')
- solution2
select a.docnum
from t0721 a
group by 1
having group_concat(status)='FULL'