How to implement sorting?

Question

PHP

Hello, the question will seem a little silly to you, but as a beginner you will help me a lot.
And so here's the problem.
There is a table of categories, with a large number of subcategories.
I need to display those with the most subcategories first.
Ie output in descending order.

using ORDER BY how to implement?

Answer 1

All categories with subcategories sort by the number of subcategories in the category in descending order

SELECT ALL COUNT(parent_id) OVER(PARTITION BY id) AS idc
    , title , key ,desc , parent_id,id
FROM test order by idc desc

Only categories (id) sort by the number of categories subcategories in descending order

SELECT DISTINCT COUNT(parent_id) OVER(PARTITION BY id) idc
, id
FROM test order by idc desc