doucong1992 2013-07-14 14:18
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Mysql按其他表的结果排序(COUNT ROWS OF TABLE 2)[关闭]

TABLE 1

SELECT * FROM page WHERE public = 1 order by*****results of table 2****** ASC

table 2

SELECT * FROM abonnement where page_id = $page_id AND (date > NOW() OR gratis = 1)

COUNT ROWS TABLE 2 AND PUT IT IN TABLE 1 ORDER BY....

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  • dp19001 2013-07-14 14:36
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    It sounds like you need a group by and a left outer join:

    SELECT p.*
    FROM page p 
    LEFT OUTER JOIN
         (SELECT page_id, COUNT(*) AS cnt
          FROM abonnement
          WHERE (date > NOW() OR gratis = 1)
          GROUP BY page_id
         ) a
         ON p.page_id = a.page_id
    WHERE p.public = 1
    ORDER BY a.cnt ASC;
    

    The left outer join ensures that you do not lose any rows in page in case there are no matching rows in the second query.

    Also note that I removed the condition page_id = $page_id. That is replaced by the on clause.

    I would also suggest include a.cnt in the select clause so you actually see the count.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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