返回所有重复行

Question

我编写了这段代码来查找重复项，它工作得很好：

SELECT *
FROM StyleTable 
GROUP BY Color
HAVING count(*) > 1 

问题是，它只返回重复行之一。是否可以返回所有重复的行？我猜这可能与“GROUP BY”有关，但我不确定如何更改它。我不想删除这些值，只是返回它们。

Answer 1

你必须再次加入表才能获得我认为的重复项。比如：

SELECT * 
FROM StyleTable 
WHERE Color IN (
  SELECT Color  
  FROM StyleTable   
  GROUP BY Color  
  HAVING count(*) > 1 
)     

Answer 2

SELECT s.*
    FROM StyleTable s
        INNER JOIN (SELECT Color
                        FROM StyleTable
                        GROUP BY Color
                        HAVING COUNT(*) > 1) q
            ON s.Color = q.Color

Answer 3

WITH cte AS ( SELECT FirstName, LastName,COUNT(*) occurrences FROM Customer GROUP BY FirstName, LastName HAVING COUNT(*) > 1)
SELECT * FROM Customer INNER JOIN cte ON 
        cte.FirstName = Customer.FirstName AND 
        cte.LastName = Customer.LastName
ORDER BY Customer.FirstName, Customer.LastName

Answer 4

我遇到了类似的问题，并使用 CTE 仅选择给定列具有多个条目的行。

表中

Bread

和

Butter

有多行；巧克力是独一无二的。

此演示查询仅返回重复行

用于重新创建示例的 SQL 语句

创建表格

CREATE TABLE Duplicates 
(
   ProductID INTEGER PRIMARY KEY AUTOINCREMENT,
   Name TEXT,
   Price REAL
);

插入一些记录

INSERT INTO Duplicates (Name, Price) VALUES ('Bread', '1.01');
INSERT INTO Duplicates (Name, Price) VALUES ('Chocolate', '3.03');
INSERT INTO Duplicates (Name, Price) VALUES ('Bread', '10.20');
INSERT INTO Duplicates (Name, Price) VALUES ('Butter', '2.02');
INSERT INTO Duplicates (Name, Price) VALUES ('Cherry', '7.03');
INSERT INTO Duplicates (Name, Price) VALUES ('Butter', '20.20');

查询

WITH CTE AS (
    SELECT Name, Price FROM Duplicates
)
SELECT * FROM CTE 
         WHERE Name in (
               SELECT Name FROM Duplicates 
               Group BY Name HAVING Count(Name)>1
         );