Question

我有一个数据库：database，其中包含一个表：table和一些字段：

id  fname       dphone      count_pic   dup_id  

6055903 Karla       5126xxx798  1       57  
6173767 Aaliyah     4082xxx534  4       39  
5611411 Aaliyah     4082xxx534  15      39  
5611211 Aaliyah     4082xxx534  18      39  
4234798 Abby        3057xxx974  31      16  
6166691 Walter      6178xxx280  1       74  
3375576 Walter      6178xxx280  17      74

我要做的是选择count_pic最小的字段和count_pic更大且dup_id

的字段

如何在mysql中做到这一点？

感谢。

Answer 1

使用此查询，您将为每count_pic

选择dup_id的最小值和最大值

  SELECT MIN(count_pic) AS minpic,
         MAX(count_pic) AS maxpic,
         dup_id
    FROM `table`
GROUP BY dup_id

如果您还需要相应的行，那么您可以使用类似

的内容

    SELECT *
      FROM `table` t1
INNER JOIN (SELECT MIN(count_pic) AS minpic,
                   MAX(count_pic) AS maxpic,
                   dup_id
              FROM `table`
          GROUP BY dup_id) t2 ON t1.dup_id = t2.dup_id
                             AND (t1.count_pic = minpic
                               OR t1.count_pic = maxpic)

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1 个答案: