sql issue - need table join

[whatson]

I am trying to do a table join, but I am trying to join the same table on to itself.

I am not sure how this achieved, or if there is an easy way to do it.

so I have

SELECT `categories_id`,`categories_name`,`parent_id` FROM `categories`

But I want the results to map the category name on to the category ID, so the results show the category name, instead of ID.
Currently I have to do an extra request in the while loop

SELECT `categories_name` FROM `categories` WHERE `categories_id`=$subcat_id

Any suggestions? I am sure its really simple.

[LifeinAsia]

Kind of confused... You're already pulling the categories_name in the query. Why don't you just display it?

[whatson]

But I need to match the category name on the the id
A sample row is like this
id cat_id name
1 0 Mercedes
2 1 A Class

And I want to pull
2 Mercedes A Class

[topr8]

to join a table to itself you use aliases:

SELECT a.id,b.name,a.name FROM categories as a,categories as b WHERE a.cat_id=b.id