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Kotlin-based LeetCode algorithm problem solutions, regularly updated

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584\. Find Customer Referee

Easy

SQL Schema

Table: `Customer`

    +-------------+---------+
    | Column Name | Type    |
    +-------------+---------+
    | id          | int     |
    | name        | varchar |
    | referee_id  | int     |
    +-------------+---------+
    id is the primary key column for this table.
    Each row of this table indicates the id of a customer, their name, and the id of the customer who referred them. 

Write an SQL query to report the IDs of the customer that are **not referred by** the customer with `id = 2`.

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

The query result format is in the following example.

**Example 1:**

**Input:**

    Customer table:
    +----+------+------------+
    | id | name | referee_id |
    +----+------+------------+
    | 1  | Will | null       |
    | 2  | Jane | null       |
    | 3  | Alex | 2          |
    | 4  | Bill | null       |
    | 5  | Zack | 1          |
    | 6  | Mark | 2          |
    +----+------+------------+

**Output:**

    +------+
    | name |
    +------+
    | Will |
    | Jane |
    | Bill |
    | Zack |
    +------+