A Database Error Occurred

Error Number: 1054

Unknown column 'c.output' in 'where clause'

SELECT distinct c.* FROM (`content_live` c) INNER JOIN `content` cl ON cl.id = c.id and cl.online=1 INNER JOIN `linkxrefs` l ON l.linkid = c.cat0id and l.tableid = 'category' WHERE l.contentid = '8453' AND c.typeid = '157' AND MATCH(c.output,c.view) AGAINST('pdf true ' IN BOOLEAN MODE) ORDER BY c.name