Last updated on October 5th, 2024 at 04:36 pm
This Leetcode problem Delete Duplicate Emails LeetCode Solution is done in SQL.
List of all LeetCode Solution
Level of Question
Easy
Delete Duplicate Emails LeetCode Solution
Table of Contents
Problem Statement
Column Name | Type |
id | int |
varchar |
Person
id is the primary key (column with unique values) for this table. Each row of this table contains an email. The emails will not contain uppercase letters.
Write a solution to delete all duplicate emails, keeping only one unique email with the smallest id
.
For SQL users, please note that you are supposed to write a DELETE
statement and not a SELECT
one.
For Pandas users, please note that you are supposed to modify Person
in place.
After running your script, the answer shown is the Person
table. The driver will first compile and run your piece of code and then show the Person
table. The final order of the Person
table does not matter.
The result format is in the following example.
Example 1:
Input:
id | |
1 | john@example.com |
2 | bob@example.com |
3 | john@example.com |
Output:
id | |
1 | john@example.com |
2 | bob@example.com |
Explanation: john@example.com is repeated two times. We keep the row with the smallest Id = 1.
1. Delete Duplicate Email LeetCode Solution MySQL
delete p1 from Person as p1, Person as p2 where p1.Email = p2.Email and p1.Id > p2.Id;