Mysql function: GROUP_CONCAT() (Like implode() in php)

Today i have to solve a problem in MySql , The problem is i have two table in openCart
1. category_description

category_id	language	name
1	1	category 1
2	1	category 2
3	1	category 3
4	1	category 4
5	1	category 5
6	1	category 6
7	1	category 7
8	1	category 8

1. product_category

produc_id	category_id
1	1
1	2
1	5
2	1
2	3
2	4
3	2
3	6

The resulting data should be like that

produc_id	category_name
1	category 1,category 2,category 5
2	category 1,category 3,category 4
3	category 2,category 6

I can do tha by in php by taking the category name to it's respective product id and implode them , but it will take much time and processor power cos the i have to do query every product id separately, I was searching the right query in MySql and found the function   GROUP_CONCAT() http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat

SELECT pc.product_id,GROUP_CONCAT(DISTINCT cd.name) category_name FROM product_to_category pc LEFT JOIN category_description cd ON (pc.category_id=cd.category_id) WHERE cd.language_id =1 GROUP BY pc.product_id And made the query i was looking for and solved my problem :)

Mysql function: GROUP_CONCAT()  (Like implode() in php)