本文介绍了删除 SQL 中除第一条记录外的重复记录的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我想删除除第一个之外的所有重复记录.
I want to remove all duplicate records except the first one.
喜欢:
NAME
R
R
rajesh
YOGESH
YOGESH
现在我想删除上面的第二个R"和第二个YOGESH".
Now in the above I want to remove the second "R" and the second "YOGESH".
我只有一列名称为NAME".
I have only one column whose name is "NAME".
推荐答案
使用 CTE(我有几个在生产中).
Use a CTE (I have several of these in production).
;WITH duplicateRemoval as (
SELECT
[name]
,ROW_NUMBER() OVER(PARTITION BY [name] ORDER BY [name]) ranked
from #myTable
ORDER BY name
)
DELETE
FROM duplicateRemoval
WHERE ranked > 1;
说明:CTE 将获取您的所有记录并为每个唯一条目应用一个行号.每个额外的条目将获得一个递增的数字.将 DELETE 替换为 SELECT * 以查看它的作用.
Explanation: The CTE will grab all of your records and apply a row number for each unique entry. Each additional entry will get an incrementing number. Replace the DELETE with a SELECT * in order to see what it does.
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