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Java-based LeetCode algorithm problem solutions, regularly updated

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196\. Delete Duplicate Emails

Easy

SQL Schema

Table: `Person`

    +-------------+---------+
    | Column Name | Type    |
    +-------------+---------+
    | id          | int     |
    | email       | varchar |
    +-------------+---------+
    id is the primary key column for this table.
    Each row of this table contains an email. The emails will not contain uppercase letters. 

Write an SQL query to **delete** all the duplicate emails, keeping only one unique email with the smallest `id`.

Return the result table in **any order**.

The query result format is in the following example.

**Example 1:**

**Input:**

    Person table:
    +----+------------------+
    | id | email            |
    +----+------------------+
    | 1  | [email protected] |
    | 2  | [email protected]  |
    | 3  | [email protected] |
    +----+------------------+

**Output:**

    +----+------------------+
    | id | email            |
    +----+------------------+
    | 1  | [email protected] |
    | 2  | [email protected]  |
    +----+------------------+

**Explanation:** [email protected] is repeated two times. We keep the row with the smallest Id = 1.