使用SQL Server在表中查找重复记录

Question

我正在验证一个包含电子商务网站的交易级别数据的表格,并找到确切的错误.

我希望您的帮助在SQL Server上的50列表中查找重复记录.

假设我的数据是:

OrderNo shoppername amountpayed city Item       
1       Sam         10          A    Iphone
1       Sam         10          A    Iphone--->>Duplication to be detected
1       Sam         5           A    Ipod
2       John        20          B    Macbook
3       John        25          B    Macbookair
4       Jack        5           A    Ipod

假设我使用以下查询:

Select shoppername,count(*) as cnt
from dbo.sales
having count(*) > 1
group by shoppername

会回来的

Sam  2
John 2

但我不想找到重复超过1或2列.我想在我的数据中找到所有列的副本.我希望结果如下:

1       Sam         10          A    Iphone

Answer 1

with x as   (select  *,rn = row_number()
            over(PARTITION BY OrderNo,item  order by OrderNo)
            from    #temp1)

select * from x
where rn > 1

您可以通过替换select语句来删除重复项

delete x where rn > 1

Answer 2

SELECT OrderNo, shoppername, amountPayed, city, item, count(*) as cnt
FROM dbo.sales
GROUP BY OrderNo, shoppername, amountPayed, city, item
HAVING COUNT(*) > 1

Answer 3

只需将所有字段添加到查询中，并记住将它们也添加到分组依据中。

Select shoppername, a, b, amountpayed, item, count(*) as cnt
from dbo.sales
group by shoppername, a, b, amountpayed, item
having count(*) > 1