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mysql - GROUP BY 另一个已经用两个子查询分组的表

问题描述

我有这样的桌子

Table1

ID      |    Val         |     Val2       |
606541  |3175031503131004|3175032612900004|
606542  |3175031503131004|3175032612900004|
677315  |3175031503131004|3175032612980004|
222222  |1111111111111111|8888888888888888|
231233  |1111111111111111|3175032612900004|
111111  |9999992222211111|1111111111111111|
57      |3173012102121018|3173015101870020|
59      |3173012102121018|3173021107460002|
2       |900             |7000            |
4       |900             |7001            |

我有两个条件与列Val和Val2。显示结果，如果Val：

  1. Val 列至少有两个或多个重复值AND
  2. Val2 列没有重复值（唯一）

例如 ：

样品 1

 ID      |    Val         |     Val2       |
 606541  |3175031503131004|3175032612900004|
 606542  |3175031503131004|3175032612900004|  
 677315  |3175031503131004|3175032612980004|

 False, because  even the Val column 
 had two or more duplicate but the Val2 
 had dulicate value (ID 606541  and 606542)

预期样本 1 个结果

 No records

样品 2

 ID      |    Val         |     Val2       |
 222222  |1111111111111111|8888888888888888|
 231233  |1111111111111111|3175032612900004|   
 111111  |9999992222211111|1111111111111111|

 True, Because the condition is match, 
 Val column had duplicate value AND Val2 had unique values

样本 2 预期结果

 ID      |    Val         |     Val2       |
 222222  |1111111111111111|8888888888888888|
 231233  |1111111111111111|3175032612900004|

样品 3

 ID      |    Val         |     Val2       |
 606541  |3175031503131004|3175032612900004|
 606542  |3175031503131004|3175032612900004|
 677315  |3175031503131004|3175032612980004|
 222222  |1111111111111111|8888888888888888|     
 231233  |1111111111111111|3175032612900004|
 111111  |9999992222211111|1111111111111111|

 Note : This is false condition, Because even the value for id 606541, 606542, and
 677315 in column Val had duplicate value at least 
 two or more but the value in column Val2 had no unique value (it could be true condition if id 606541, 
 606542, and 677315 had 3 different value on Val2).

 NOte 2 : for Id 222222 and 231233 that had duplicate value, this is still false, because the column 
 Val2 with ID 231233 had the same value with ID 606542 and 606541 (3175032612900004), so it didnt match 
 the second condition which only have no duplicate value

样本 3 预期结果

 No records

现在回到Table1前面，我尝试使用此查询显示两个条件的结果

SELECT
tb.* FROM table1 tb 
WHERE
    tb.Val2 IN (
    SELECT ta.Val2 
    FROM (
        SELECT
            t.* 
        FROM
            table1 t 
        WHERE
            t.Val IN ( 
            SELECT Val FROM table1 
            GROUP BY Val 
            HAVING count( Val ) > 1 ) 
        ) ta 
    GROUP BY
        ta.Val2 
    HAVING
    count( ta.Val2 ) = 1 
    )

结果

ID         Val                   Val2
677315  3175031503131004    3175032612980004
222222  1111111111111111    8888888888888888
57      3173012102121018    3173015101870020
59      3173012102121018    3173021107460002
2       900                  7000            
4       900                  7001

虽然我希望结果是这样的：

ID         Val                   Val2
57  3173012102121018    3173015101870020
59  3173012102121018    3173021107460002
2       900             7000            
4       900             7001

我的查询有问题吗？

这是我的数据库小提琴。

标签： mysqlsqlgroup-byconditional-statementshaving-clause

解决方案

您必须使用Group By来查找val&val2具有重复值，并且需要使用Inner JoinandLeft Join来包含/消除作为给定条件的记录（反对IN,NOT IN等在处理大数据时可能导致性能问题的子句）。

请在下面找到查询：

select t1.*from table1 t1 left join
      (select val from table1
       where val2 in (select val2 from table1 group by val2 having count(id) > 1)
        ) t2
 on t1.val = t2.val
 inner join
     (select val from table1 group by val having count(id) >1) t3
     on t1.val = t3.val
 where t2.val is null

查询反向条件：

select t1.*from table1 t1 inner join
       (select val from table1 group by val having count(id) = 1)
         t2
 on t1.val = t2.val
 inner join
     (select val2 from table1 group by val2 having count(id) >1) t3
     on t1.val2 = t3.val2

请在此处找到两个查询的小提琴。

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