SELECT file_id

FROM img_link l, img_tags t

WHERE t.id=l.tags_id 
AND t.tag = '%s'

This fetches all file_id's with a tag associated of '%s'
How do I fetch all file_id's that are associated with more than one tag
I keep wanting to do AND t.tag = '%s' AND t.tag = '%s' but I know thats wrong. Halp?