with recursive in mysql does not work with me

I have the following database schema

Course (id, fullname, shortname, category) Category (id, name , parent)

I want to make a select statement that concat all categories name of the course from leaf to top parent with id = 0

I have asked and some one advice me to use with recursive in mysql and he helped me with sample code to my problem and I have adjusted it to my schema

here is the code

with recursive
n as (
  select mc.id, mc.fullname , mc.shortname , mcc.name  as category, mcc.parent 
  from mdl_course mc
  join mdl_course_categories mcc on mcc.id = mc.category 
 union all
  select n.id, n.fullname, n.shortname, concat(n.category, ' - ', mcc.name) as category , mcc.parent 
  from n
  join mdl_course_categories mcc on mcc.id  = n.parent
)
select id, fullname, shortname, category from n

when I run the query it does not give error, but it only show the leaf category and did not make any recursive or contamination

can anyone help please?

EDIT

CREATE TABLE `mdl_course` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `category` bigint(20) NOT NULL DEFAULT 0,
  `sortorder` bigint(20) NOT NULL DEFAULT 0,
  `fullname` varchar(254) NOT NULL DEFAULT '',
  `shortname` varchar(255) NOT NULL DEFAULT ''
  )

and for Course Category

CREATE TABLE `mdl_course_categories` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL DEFAULT '',
  `idnumber` varchar(100) DEFAULT NULL,
  `description` longtext DEFAULT NULL,
  `descriptionformat` tinyint(4) NOT NULL DEFAULT 0,
  `parent` bigint(20) NOT NULL DEFAULT 0
  )