LeetCode 196. Delete Duplicate Emails

  1. Delete Duplicate Emails My Submissions QuestionEditorial Solution
    Total Accepted: 14121 Total Submissions: 73321 Difficulty: Easy
    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 | [email protected] |
| 2 | [email protected] |
| 3 | [email protected] |
+—-+——————+
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 | [email protected] |
| 2 | [email protected] |
+—-+——————+

刚开始看数据库,借鉴了别人一下

delete from Person where Id not in 
(select A.Id from (select min(Id) as Id from Person group by Email) A);

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