Question

我有一个表有2个重复行（总共3行），所以我使用下面的代码来获取列中的重复值

SELECT CustNo, COUNT(*) TotalCount
FROM Rental
GROUP BY CustNo
HAVING COUNT(*) > 1
ORDER BY COUNT(*) DESC

因此，一旦我获得重复值，我需要从客户表中获取作为重复派生的CustNo。如何获取此值并在同一查询中的选择语句中使用它。我也有像这样准备的选择声明。

Select *  from Customer where  CustNo = 'T0002';

感谢。

Answer 1

Select * from Customer 
where CustNo IN
(
  SELECT CustNo
  FROM Rental
  GROUP BY CustNo
  HAVING COUNT(*) > 1
)

Answer 2

您可以使用join：

SELECT c.*
FROM (SELECT CustNo, COUNT(*) TotalCount
      FROM Rental
      GROUP BY CustNo
      HAVING COUNT(*) > 1
     ) cc JOIN
     Customer c
     on cc.CustNo = c.CustNo;

Answer 3

Select C.*  from Customer C RIGHT JOIN (
SELECT CustNo
FROM Rental
GROUP BY CustNo
HAVING COUNT(*) > 1) D
ON C.CustNo = D.CustNo

Answer 4

你也可以试试这个，

以tblDups为（选择CustNo，从a_rental计算（CustNo）为TotalCount 由CustNo分组有计数（CustNo）＆gt; 1）

从a_rental b中选择b。* 内部联接tblDups a on a.CustNo = b.Custno

来自另一个表的行值

4 个答案: