How to compose a Mysql query without using WITH?

Question

MySQL

There is a plate
| id | email | partner_id |
partner_id -> this is a connection with a record from the same table.
The task is to find out all the lower "partners", while getting the level of depth at which they are.
MySql Doesn't support WITH, How to rewrite a query for MYSQL?

WITH list AS
 (SELECT upper.id, upper.email, upper.partner_id,
 1 AS level
 FROM users AS upper
 WHERE upper.partner_id IS NULL

 UNION ALL

 SELECT lower.id, lower.email lower.partner_id,
 el.level + 1
 FROM users AS lower
 INNER JOIN list AS el
 ON lower.partner_id = el.id
 WHERE lower.partner_id IS NOT NULL)
SELECT * 
FROM list;

Answer 1

with works recursively - doing thousands of queries is very inefficient.
It is better to change the structure of the table. Google "storing a tree in a database"
Or at least make one complete select and then build an array-tree on your PL (for example, PHP).