Tag result empty- which table is used to sotre post tags?

Hi all I am changing some sql code and when I run it in the mysql gui with the wordpress database I get 0 tags. Where are the tags stored? Thank you `select c.name as tag
from wp_posts a, wp_term_relationships b, wp_terms c, wp_term_taxonomy d
where a.ID = b.object_id
and b.term_taxonomy_id = c.term_id
and c.term_id = d.term_id
and d.taxonomy = ‘post_tag’
and a.post_status=’publish’
`