category/database error.

I got this message when I tried to click on a category link on my blog. This never happend before, I was just checking today if all my links are working, but apparently, there’s something wrong. I am not familiar with fixing databases and stuff, so please do help me… and walk me through it. thanks a bunch.

here’s the error message by the way!

WordPress database error: [Got error 28 from storage engine]
SELECT wp_posts.* FROM wp_posts LEFT JOIN wp_post2cat ON (wp_posts.ID = wp_post2cat.post_id) WHERE 1=1 AND wp_post2cat.category_id IN (6) AND (post_type = ‘post’ AND (post_status = ‘publish’ OR post_status = ‘future’ OR post_status = ‘draft’ OR post_status = ‘private’)) GROUP BY wp_posts.ID ORDER BY post_date DESC