Yii2. How to display all subcategories?

Question

Yii

There is a category table.
For example, I select the CLOTHING category, and therefore, the page should display both "T-shirts" and "Polo shirts" and "sleeveless T-shirts" and "T-shirts with sleeves". That is, all subcategories below the selected one.
So, is it possible to get all these categories (namely those below) with one request?
the result should be:

Array
(
    [0] => Array
    (
        [id] => 1
        [name] => Одежда
    )

    [1] => Array
    (
        [id] => 2
        [name] => футболки
    )

    [2] => Array
    (
        [id] => 3
        [name] => футболки-поло
    )

    [3] => Array
    (
        [id] => 4
        [name] => футболки без рукавов
    )

    [4] => Array
    (
        [id] => 5
        [name] => футболки с рукавами
    )
)

You can, of course, use recursion, but suddenly there is a special way in yii.
Thanks in advance!

Answer 1

One request will not solve this problem in any way. You have such a category tree storage model that only recursion can be used here. If you want to select everything with one request, change the tree storage model, for example, to Nested Sets

Answer 2

Good afternoon.
Use the model link on itself.

public function getParent()
{
   retun $this->hasMany(ModelName::class, ['parent_id' => 'id']);
}

In the query, use with('parent')
Read more here .

Answer 3

well, not all the developers of the framework should do it for the programmers)))) I think special. There are no ways

Answer 4

This type of storage is called Adjacency List.
Here is an extension for yii from PaulZi: https://github.com/paulzi/yii2-adjacency-list
Here I analyzed it in a video: https://youtu.be/1BQrCbLTeuw