update tourism_catlinks join tourism_links on tourism_links.id = tourism_catlinks.LinkID_tourism_catlinksjoin tourism_category on tourism_links.geo_town = tourism_links.geo_town and tourism_links.geo_county = tourism_links.idset tourism_links.LinkID = tourism_links.id^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Your SQL ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^update tourism_catlinks join tourism_links on tourism_links.id = tourism_catlinks.LinkIDjoin tourism_category on tourism_links.geo_town = tourism_links.geo_town and tourism_links.geo_county = tourism_links.idset tourism_catlinks.LinkID = tourism_links.id^ Edited SQL, had to drop the second part of tourism_catlinks.LinkID_tourism_catlinks due to 'unknown column'