Database error with query: [ SELECT a.*, c.name as cat_name,c.id as cat_id, a.article_date as art_date,c.type, theme, rel_id, if (a.ngo = 'N', if(TO_DAYS(now())-TO_DAYS(a.article_date)<365, 1, 0.5), 1) AS YearPenalty, if(TO_DAYS(now())-TO_DAYS(a.article_date)<40, FLOOR(2*POWER(40-(TO_DAYS(now())-TO_DAYS(a.article_date)),2)),0) AS AgeBonus, (if(TO_DAYS(now())-TO_DAYS(a.article_date)<40, FLOOR(2*POWER(40-(TO_DAYS(now())-TO_DAYS(a.article_date)),2)),0) + Max(score)) * if (a.ngo = 'N', if(TO_DAYS(now())-TO_DAYS(a.article_date)<365, 1, 0.5), 1) AS MaxOfscore FROM ( SELECT DISTINCT articles.id as art_id, articles.article_date as article_date, articles.source as source, articles.author as author, articles.title as title, relevances.theme as theme, (relevance_1.relevance) * (relevances.relevance) as score, relevances.relevance AS thispage, relevance_1.relevance AS linkedpage, relevance_1.article_id as rel_id FROM relevances, relevances as relevance_1 INNER JOIN articles ON relevances.article_id = articles.id WHERE (relevance_1.article_id != relevances.article_id) and (articles.id ='889') AND (relevance_1.theme = relevances.theme) ORDER BY score DESC, article_date DESC ) as details, articles as a LEFT JOIN article_cats c ON c.id=a.type_id WHERE a.id = rel_id AND (status<>'closed') GROUP BY title, rel_id ORDER BY MaxOfscore DESC, article_date DESC]: error 1054:Unknown column 'relevances.article_id' in 'on clause'