LeetCode 0196 - Delete Duplicate Emails
LeetCode 0196 - Delete Duplicate Emails
Reck Zhang
发布于 2021-08-11 13:24:31
发布于 2021-08-11 13:24:31
文章被收录于专栏：Reck Zhang
Delete Duplicate Emails
Desicription
Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.
+----+------------------+
| Id | Email |
+----+------------------+
| 1 | john@example.com |
| 2 | bob@example.com |
| 3 | john@example.com |
+----+------------------+
Id is the primary key column for this table.For example, after running your query, the above Person table should have the following rows:
+----+------------------+
| Id | Email |
+----+------------------+
| 1 | john@example.com |
| 2 | bob@example.com |
+----+------------------+Solution
# Write your MySQL query statement below
DELETE
P1
FROM
Person P1, Person P2
WHERE
P1.Email = P2.Email AND
P1.Id > P2.Id本文参与 腾讯云自媒体同步曝光计划，分享自作者个人站点/博客。
原始发表：2018-06-11，如有侵权请联系 cloudcommunity@tencent.com 删除
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