MySQL查询最上层父节点

    在MySQL数据库中，有时候我们需要查询某个节点的最上层父节点。假设我们有一个名为`ree`的表格，它包含以下字段：

     `id`: 节点的唯一标识符

     `pare_id`: 父节点的id，如果该节点是根节点，则pare_id为ULL

     `ame`: 节点的名称

    我们需要建立数据库和表格：

    1. 创建数据库：

    ```sql

    CREATE DATABASE ree_example;

    ```

    2. 使用数据库：

    ```sql

    USE ree_example;

    ```

    3. 创建表格：

    ```sql

    CREATE TABLE ree (

     id IT PRIMARY KEY,

     pare_id IT,

     ame VARCHAR(100),

     FOREIG KEY (pare_id) REFERECES ree(id)

    );

    ```

    接下来，我们插入一些数据：

    假设我们有以下节点：

     ID: 1, Pare ID: ULL, ame: Roo

     ID: 2, Pare ID: 1, ame: A

     ID: 3, Pare ID: 1, ame: B

     ID: 4, Pare ID: 2, ame: C

     ID: 5, Pare ID: 2, ame: D

     ID: 6, Pare ID: 3, ame: E

     ID: 7, Pare ID: 3, ame: F

     ID: 8, Pare ID: 4, ame: G

     ID: 9, Pare ID: 4, ame: H

     ID: 10, Pare ID: 5, ame: I

     ID: 11, Pare ID: 5, ame: J

     ID: 12, Pare ID: 6, ame: K

     ID: 13, Pare ID: 6, ame: L

     ID: 14, Pare ID: 7, ame: M

     ID: 15, Pare ID: 7, ame:

     ID: 16, Pare ID: 8, ame: O

     ID: 17, Pare ID: 8, ame: P

     ID: 18, Pare ID: 9, ame: Q

     ID: 19, Pare ID: 9, ame: R

     ID: 20, Pare ID: 10, ame: S

     ID: 21, Pare ID: 10, ame: T

     ID: 22, Pare ID: 11, ame: U

     ID: 23, Pare ID: 11, ame: V

     ID: 24, Pare ID: 12, ame WXY (his is he ode we wa o fid he op pare for)Zu003e To fid he op pare for he ode wih he ame 'WXY', we eed o wrie a query ha recursively checks he pare_id uil i fids a pare_id ha is ULL. Here's a example query ha accomplishes his ask:u003c/reeu003eSELECT 1.ame AS op_pare_ameFROM ree 1JOI ree 2 O 1.id =

    2.pare_idWHERE

    2.ame = 'WXY'AD 1.pare_id IS ULLu003c/reeu003eTo execue his query ad rerieve he resul i a programmig laguage of your choice (e.g., Pyho), you ca use a MySQL coecor library such as PyMySQL:u003c/pyhou003eimpor pymysqlco = pymysql.coec(hos='localhos', user='userame', password='password', db='ree_example')cursor = co.cursor()query = 2 O 1.id =

    2.pare_id WHERE

    2.ame = 'WXY' AD 1.pare_id IS ULLoe()[0]pri(f creaig a idex o he `pare_id` colum.u003c/reeu003e