SELECT a.event_name AS event_name, a.event_date AS event_date,
a.event_venue AS event_venue, a.event_tparticipant AS event_tparticipant,
b.username AS username
FROM (SELECT * FROM event WHERE status = 'valid') AS a
JOIN
(
SELECT COUNT(DISTINCT username) AS username
FROM event_participant
GROUP BY event_name
) AS b
GROUP BY event_name desc
내 문제는 사용자 이름을 계산할 때 내 데이터베이스의 정확한 금액이 아닙니다. 제발 도와주세요
검색어에 join조건 이 없습니다 . 아래에서 시도해보십시오.
SELECT
a.event_name as event_name, a.event_date as event_date,
a.event_venue as event_venue,
a.event_tparticipant as event_tparticipant,
b.username as username
FROM (select * from event WHERE status='valid') as a
JOIN (select event_name, COUNT(DISTINCT username) as username
from event_participant
GROUP BY event_name) as b
ON a.event_name = b.event_name --change this condition to be appropriate
GROUP BY event_name desc
이 기사는 인터넷에서 수집됩니다. 재 인쇄 할 때 출처를 알려주십시오.
침해가 발생한 경우 연락 주시기 바랍니다[email protected] 삭제
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