匹配 2 列中的重复值和 1 列中的 1 个唯一值 mysql

Question

我有这个table，这是我的db Fiddle

CREATE TABLE table1 (
  `ID` VARCHAR(100),
  `Val` VARCHAR(100),
  `Val2` VARCHAR(100),
  `Val3` VARCHAR(100)
);

INSERT INTO table1
  (`ID`, `Val`, `Val2`, `Val3`)
VALUES
  ('1','100','200','90'),
  ('2','100','200','10'),
  ('3','100','200','20'),
  ('4','20','100','55'),
  ('5','20','100','10'),
  ('6','112','100','20'),
  ('7','112','100','20'),
  ('8','90','200','90'),
  ('9','30','90','180'),
  ('10','30','90','29');

我想要这个条件下的结果

Val 必须是重复的 AND
Val2 必须重复 AND

在我得到重复值之后，现在我需要检查重复值中的 val3，如果 val3 的 值具有来自先前聚合的唯一值

我试过这个查询

SELECT
    t1.* 
FROM
    table1 t1 
WHERE
    EXISTS (
    SELECT
        1 
    FROM
        table1 
    WHERE
        ID <> t1.ID 
        AND Val = t1.Val 
        AND Val2 = t1.Val2 
    ) 
    AND NOT EXISTS (
    SELECT
        1 
    FROM
        table1 
    WHERE
        Val = t1.Val 
        AND Val2 = t1.Val2 
    AND Val3 IN ( 
    SELECT Val3 
    FROM table1 
    GROUP BY Val3 
    HAVING count( * ) > 1 
    ) 
)

我希望结果是这样的

ID  Val Val2    Val3
1   100 200 90
2   100 200 10
3   100 200 20
4   20  100 55
5   20  100 10
9   30  90  180
10  30  90  29

但是我得到了这样的结果

ID  Val Val2    Val3
9   30  90  180
10  30  90  29

示例 2

INSERT INTO table1
  (`ID`, `Val`, `Val2`, `Val3`)
VALUES
  ('1','100','200','90'),
  ('2','100','200','10'),
  ('3','100','200','20'),
  ('19','100','200','20'),
  ('4','20','100','55'),
  ('5','20','100','10'),
  ('6','112','100','20'),
  ('7','112','100','20'),
  ('8','90','200','90'),
  ('9','30','90','180'),
  ('10','30','90','29');

预期结果2

ID  Val Val2    Val3
1   100 200 90
2   100 200 10
4   20  100 55
5   20  100 10
9   30  90  180
10  30  90  29

dbfiddle 2

示例 3

INSERT INTO table1
  (`ID`, `Val`, `Val2`, `Val3`)
VALUES
  ('1','100','200','aa'),
  ('2','100','200','aa'),
  ('3','100','200','aa'),
  ('19','100','200','ab'),
  ('4','20','100','SD2'),
  ('5','20','100','SD1'),
  ('6','112','100','aa'),
  ('7','112','100','ab'),
  ('8','90','200','aa'),
  ('9','30','90','SF2'),
  ('10','30','90','SF1');

预期结果3

ID  Val Val2    Val3

4   20  100 SD2
5   20  100 SD1
6   112 100 aa
7   112 100 ab
9   30  90  SF2
10  30  90  SF1

有些人可能对样本 3 感到困惑，所以这里是样本 3 的注释：

对于这种情况，示例 3 中的 ID 19 与列 val 和 val2 的 id 1、2、3（100 和 200）具有相同的值，但是这些 id (1、2、3) 具有相同的 aa value in val3，所以必须排除id 1,2,3，因为这些id没有匹配上一个条件(val, val2, val3) 是唯一的。 ID 19 很好，但是 val dan val2 具有重复值的列，即 id 1,2，并且 3 已经被排除，这使得 id 19 对于列 val 和 val2 都没有重复值。如果样本 3 中有另一个数据，如 '200'、'100'、'200'、'ae'，则 id 19 将包含在结果中，因为它在 id 1,2 和 3 旁边具有重复值。

对于示例 3，如果 table1 中的数据是这样的，则 ID 19 将被包含在内

示例 3（不同大小写）

INSERT INTO table1
  (`ID`, `Val`, `Val2`, `Val3`)
VALUES
  ('1','100','200','aa'),
  ('2','100','200','aa'),
  ('3','100','200','aa'),
  ('19','100','200','ab'),
  ('200','100','200','ae'),
  ('4','20','100','SD2'),
  ('5','20','100','SD1'),
  ('6','112','100','aa'),
  ('7','112','100','ab'),
  ('8','90','200','aa'),
  ('9','30','90','SF2'),
  ('10','30','90','SF1');

预期的结果会是这样

ID  Val Val2    Val3

4   20  100 SD2
5   20  100 SD1
19  100 200 ab
200 100 200 ae
6   112 100 aa
7   112 100 ab
9   30  90  SF2
10  30  90  SF1

Answer 1

据我了解您的问题，您想要 (val, val2) 元组不唯一且 (val, val2, val3) 是唯一的行。

这是一种通过使用相关子查询过滤数据集来表达这一点的方法：

select t1.*
from table1 t1
where 
    (
        select count(*) 
        from table1 t2 
        where t2.val = t1.val and t2.val2 = t1.val2
    ) > 1
    and (
        select count(*)
        from table1 t2
        where t2.val = t1.val and t2.val2 = t1.val2 and t2.val3 = t1.val3
    ) = 1
order by id

为了性能，考虑在 (val, val1, val2) 上建立索引（索引中列的顺序在这里很重要）。

如果你有幸成为运行 MySQL 8.0，这可以使用window函数更简单有效地表达：

select id, val, val2, val3
from (
    select 
        t1.*,
        count(*) over(partition by val, val2) cnt_1,
        count(*) over(partition by val, val2, val3) cnt_2
    from table1 t1
) t
where cnt_1 > 1 and cnt_2 = 1

Answer 2

将 table 加入符合您条件的查询：

select distinct t.*
from (
  select val, val2
  from table1
  group by val, val2
  having count(*) > 1
) t1 
inner join (
 select val, val2, val3
  from table1
  group by val, val2, val3
  having count(*) = 1
) t2 
on t2.val = t1.val and t2.val2 = t1.val2
inner join (
 select val, val2, val3
  from table1
  group by val, val2, val3
  having count(*) = 1
) t3 
on t3.val = t1.val and t3.val2 = t1.val2 and t3.val3 <> t2.val3
inner join table1 t on t2.val = t.val and t2.val2 = t.val2 and t.val3 in (t2.val3, t3.val3)

见demo1, demo2, demo3, demo4。

Answer 3

正如@GMB 在他的回答中以相当简单的方式告诉的那样，您需要 (val, val2) 元组不唯一且 (val, val2, val3) 是唯一的行。

下面的查询应该很容易完成：

   select t.*
from table1 t
inner join
(
select t1.val, t1.val2
from table1 t1
 inner join
  (select val,val2,val3
    from table1
    group by val,val2,val3
    having count(val3) = 1
  ) t2
 on t1.val = t2.val and t1.val2 = t2.val2 and t1.val3 = t2.val3
 group by t1.val, t1.val2
 having count(distinct t1.id) > 1
) tmp
on tmp.val = t.val and tmp.val2 = t.val2
inner join
(select val,val2,val3
    from table1
    group by val,val2,val3
    having count(val3) = 1
  ) t3
 on t.val = t3.val and t.val2 = t3.val2 and t.val3 = t3.val3

请找到 Sample1, Sample2, Sample3 and Sample4 的 fiddle link。

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