Question

我有以下表格，其中有不同字段的重复记录：

CREATE TABLE Student1
    (`id` int,`status` int,`amount` int , `Name` varchar(10), `date` varchar(55))
;
    INSERT INTO Student1
    (`id`,`status`,`amount`, `Name`, `date`)
VALUES
    (1,0,4500, 'ram', '04/02/2012'),
    (2,0,2000, 'shyam', '05/09/2013'),
    (4,0,1500, 'ghanshyam', '08/11/2014'),
    (3,0,4500, 'gopal', '04/02/2012'),
    (2,0,8000, 'radheshyam', '15/11/2013'),
    (4,1,1500, 'ghanshyam', '18/10/2015'),
    (1,1,4500, 'ram', '14/02/2012'),
    (2,0,6500, 'radhe', '11/11/2014'),
    (3,1,4500, 'gopal', '14/02/2015'),
    (5,1,4500, 'gopala', '04/02/2015'),
    (5,1,4500, 'gopala', '04/02/2015'),
    (6,0,14500, 'gopal', '14/02/2015')
;

我有3个条件来过滤表格：

没有完整的重复记录
如果记录具有相同的id但不同的Name和date字段，则将所有这些记录添加到最终结果中
如果status=1为任何记录，则选择相应id
添加id与上述3个条件id不同的所有记录

我写了这个查询：

SELECT * FROM Student1 
GROUP BY id,status,amount,Name,date
HAVING COUNT(*) > 1

UNION 

SELECT * FROM Student1  Student1
WHERE id IN
(
SELECT id FROM Student1
GROUP BY id
HAVING COUNT(DISTINCT name) > 1
AND COUNT(DISTINCT date) > 1
)

UNION 

SELECT * FROM Student1  Student1
WHERE status=1 AND id IN
(
SELECT id FROM Student1
GROUP BY id
HAVING COUNT(id) >= 2
);

结果：

id  status  amount  Name    date
4   1   1500    ghanshyam   18/10/2015
1   1   4500    ram 14/02/2012
3   1   4500    gopal   14/02/2015
5   1   4500    gopala  04/02/2015
2   0   2000    shyam   05/09/2013
2   0   8000    radheshyam  15/11/2013
2   0   6500    radhe   11/11/2014

正如您所见，第一选择避免重复，第二选择记录使相同的id具有不同的Name，date，第三选择以获得id=1的记录。我使用UNION来避免重复结果。

现在我需要添加第4个查询来获取在上述所有情况下都不存在的记录id=6。

预期结果：

id  status  amount  Name    date
4   1   1500    ghanshyam   18/10/2015
1   1   4500    ram 14/02/2012
3   1   4500    gopal   14/02/2015
5   1   4500    gopala  04/02/2015
2   0   2000    shyam   05/09/2013
2   0   8000    radheshyam  15/11/2013
2   0   6500    radhe   11/11/2014
6   0   14500   gopal   14/02/2015

我需要解决第4个问题。请帮忙。

Answer 1

如果您要过滤的唯一条件是id = 6，则只需添加：

SELECT * FROM Student1 WHERE id=6;

您的请求直接转换为SQL。完整版将是：

SELECT * FROM Student1 
  GROUP BY id,status,amount,Name,date
  HAVING COUNT(*) > 1

UNION 

SELECT * FROM Student1  Student1
  WHERE id IN
  (
  SELECT id FROM Student1
  GROUP BY id
  HAVING COUNT(DISTINCT name) > 1
  AND COUNT(DISTINCT date) > 1
  )

UNION 

SELECT * FROM Student1  Student1
  WHERE status=1 AND id IN
  (
  SELECT id FROM Student1
  GROUP BY id
  HAVING COUNT(id) >= 2
  )

UNION 

SELECT * FROM Student1 WHERE id=6;

结果按要求提供，但顺序不同。 DEMO

但是，如果您希望获得未使用您的编码过滤的所有id，但您不知道其值，我会使用VIEW：

CREATE VIEW Student2 AS 
  SELECT * FROM Student1 
  GROUP BY id,status,amount,Name,date
  HAVING COUNT(*) > 1

UNION 

SELECT * FROM Student1  Student1
  WHERE id IN
  (
  SELECT id FROM Student1
  GROUP BY id
  HAVING COUNT(DISTINCT name) > 1
  AND COUNT(DISTINCT date) > 1
  )

UNION 

SELECT * FROM Student1  Student1
  WHERE status=1 AND id IN
  (
  SELECT id FROM Student1
  GROUP BY id
  HAVING COUNT(id) >= 2
);

And then query with it:

SELECT * FROM Student2

UNION 

SELECT * FROM Student1 WHERE id NOT IN (SELECT id FROM Student2);

结果是一样的。 DEMO

表多个Sql查询联盟

1 个答案: