[Leetcode] [SQL] Delete Duplicate Emails

https://leetcode.com/problems/delete-duplicate-emails/

Delete Duplicate Emails

Write a SQL query to delete all duplicate e-mail entries in a table named Person , keeping 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 has the following rows:

+----+------------------+| Id | Email            |+----+------------------+| 1  | [Email protected] | | 2  | [email protected]  | +----+------------------+

 to Table ' A.email = B.email ' First !!!! Delete  from where =  and > b.ID

The DELETE statement can no longer select the table, which is too much of a notation.

Delete  from where inch (selectfromgroupby havecount(*>  1)

[Leetcode] [SQL] Delete Duplicate Emails