查询输出为树MySQL

我的MySQL数据库中有两个表：

文件夹表

+----+----------+
| ID |   Name   |
+----+----------+
|  1 | folder 1 |
|  2 | folder 2 |
|  3 | folder 3 |
+----+----------+

和文件表

+----+--------+-----------+---------+
| ID |  Name  | ID_folder |   Ref   |
+----+--------+-----------+---------+
|  1 | file1  |         2 | ref133  |
|  2 | file 2 |         3 | ref2044 |
|  3 | file 3 |         3 | refA001 |
+----+--------+-----------+---------+

我想创建一个MySQL查询，输出以下结果：

输出：

即，首先显示一个文件夹（父文件夹），然后在每个文件夹下显示这些文件，并使用三个不同的值排序（列出文件的文件号、列出文件夹的文件夹号以及使文件夹显示在其文件之前的

isFile

值），此查询执行以下操作：

SELECT Name, Ref
FROM
    ((SELECT Name, '' as Ref, 0 AS isFile, ID as ID_folder, ID
      FROM Table1)
     UNION
     (SELECT Name, Ref, 1 AS isFile, ID_folder, ID
      FROM Table2))
AS tmp
ORDER BY ID_folder, isFile, ID;

---

你能告诉我们到目前为止你都做了些什么吗？

SELECT Name, Ref
FROM
    ((SELECT Name, '' as Ref, 0 AS isFile, ID as ID_folder, ID
      FROM Table1)
     UNION
     (SELECT Name, Ref, 1 AS isFile, ID_folder, ID
      FROM Table2))
AS tmp
ORDER BY ID_folder, isFile, ID;