Delete Duplicate Emails

Author: ignacio-chiazzo

LeetcodeProblems/Databases/Delete_Duplicate_Emails.sql

@@ -0,0 +1,29 @@
+/*
+Delete Duplicate Emails
+https://leetcode.com/problems/delete-duplicate-emails/
+
+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]  |
++----+------------------+
+Note:
+
+Your output is the whole Person table after executing your sql. Use delete statement.
+*/
+
+DELETE person FROM Person person, Person person2
+    WHERE person.email = person2.email AND person.id > person2.id;

README.md

@@ -90,6 +90,7 @@ To run a specific problem in your console, go to the file test, add the call to
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+| [Delete Duplicate Emails](LeetcodeProblems/Databases/Delete_Duplicate_Emails.sql) | Easy | https://leetcode.com/problems/delete-duplicate-emails |
 
 ### UtilsClasses