sql - 重复的电话号码

Question

由于糟糕的数据录入政策，同一客户有很多重复的电话号码。我需要编写一个查询，列出所有具有相同电话号码的客户。

谢谢你的帮助。

Answer 1

;WITH dupes AS
(
  SELECT Phone_Number
  FROM dbo.Customer_Table
  GROUP BY Phone_Number
  HAVING COUNT(*) > 1
)
SELECT c.Customer_Name, dupes.Phone_Number
  FROM dupes 
  INNER JOIN dbo.Customer_Table AS c
  ON dupes.Phone_Number = c.Phone_Number;