如何在Distinct ON上使用計數

Question

我有這個查詢已經有效，我需要為此寫計數查詢（需要分頁），並且我在使用DISTINCT ON時使用count有問題，任何人都知道正確的語法和使用方法，我已經用谷歌搜索了，但是找不到DISTINCT ON的任何計數查詢

結果，我期望此查詢已經可以正常工作的總行數

select DISTINCT on (csd.team_contest_id)
        c.id as contestId
            from contest as c
            left join company_sponsor_team as csd on csd.contest_id = c.id
            left join sponsor as s on s.id = c.sponsor_id
            left join team as d on d.id = c.team_id
            left join player as m on c.creator_id = m.id
            WHERE c.id = c.id 
            AND ((c.team_id is not null and c.sponsor_id is null and lower(d.name) LIKE LOWER(CONCAT('%TAN%')))
            OR (c.team_id is not null and c.sponsor_id is not null and lower(s.name) LIKE LOWER(CONCAT('%TAN%')))
            OR (c.team_id is null and lower(s.name) LIKE LOWER(CONCAT('%TAN%')))) AND (CURRENT_DATE < c.archive_date)

Answer 1

如果要計算行數，請使用子查詢：

select count(*)
from ( <your query here> ) x;

如果您不喜歡子查詢，可以隨時執行以下操作：

select count(distinct csd.team_contest_id)
from . . .  <the rest of your query here>;

假設csd.team_contest_id不為NULL ，則返回相同的值。