ummm...there are better ways to store the data .The database structure you currently have violates the First Normal Form of database design by saving category and subcategory in a single field. Here's a nice article about database normalization (Normalization)
I would recommend having a Category Table and a Subcategory table , the link between the both of them being the category ID , which would be the primary key of the Category table and the foreign key of the SubCategory table. Using such a strucure would mean that you would not need to use any parsing to get the data you want; all you would need is a simple SQL : 
select c.*, sc.* 
from category c, subcategory sc
where c.categoryID = sc.categoryID
and categoryID = <the category you want>

[download]
This would get you all the data related to the category you're looking for as well as all the subcategories realated to that specific category

In reply to Re: MySQL Answer by screamingeagle
in thread MySQL Answer by Anonymous Monk

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