當我試圖運行此查詢如何選擇子查詢

更多的行？我想從表格中選擇activity_id，但不包括特定用戶的最新8個activity_id。當我試圖運行此查詢如何選擇子查詢

2012-10-31 Stefan

NOT LIKE正期待一個表達式或一個值來比較而不是結果集。變化也不像是NOT IN

試試這個：

SELECT * FROM `activity` 
      WHERE user_id = 1 AND activity_id NOT IN (
        SELECT activity_id FROM activity WHERE user_id = 1 
             ORDER BY activity_id DESC LIMIT 8)

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2012-10-31 22:42:17 slash28cu

NOT沒有在子查詢的MySQL版本支持IN和限制。 – Stefan

我已經做出了自己的select語句......我如何將其更改爲delete語句？ \t \t \t \t $ SQL1 =「選擇T1。*，t2.activity_id作爲activity_id_2 \t \t \t \t \t \t \t FROM動作T1 \t \t \t \t \t \t \t左加入（選擇USER_ID，ACTIVITY_ID從活動其中USER_ID ='「。$ row ['user_id']。」'ORDER BY user_id，activity_id DESC LIMIT 8）t2 \t \t \t \t上\t \t（t1.user_id = t2.user_id AND t1.activity_id = t2.activity_id） \t \t \t \t \t \t \t其中t2.activity_id爲空 \t \t \t \t \t \t \t和t1.user_id =「」。$行[ 'user_ID的'] 「'」。 – Stefan

@Stefan。對於刪除語句，只需讓你的子查詢返回你想要刪除的activity_id值，然後：DELETE FROM activity where activity_id NOT IN（你的子查詢在這裏） – slash28cu

通過這樣解決的：

   $sql2 = "DELETE t1.* 
         FROM activity t1 
         left join (select activity_id from activity where user_id = '".$row['user_id']."' ORDER BY activity_id DESC LIMIT 8) t2 
         on (t1.activity_id = t2.activity_id) 
         where t2.activity_id is null 
         and t1.user_id = '".$row['user_id']."'";

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2012-11-02 14:05:02 Stefan

當我試圖運行此查詢如何選擇子查詢

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