select CategoryID, istopic from (
SELECT
CategoryID,
EXISTS (SELECT * from topics_equivalence te WHERE te.categoryid=acl.categoryid) as istopic
FROM
eZArticle_ArticleCategoryLink acl
WHERE
acl.ArticleID=110148
) as subquery select CategoryID, istopic from (
SELECT
CategoryID,
EXISTS (SELECT * from topics_equivalence te WHERE te.categoryid=acl.categoryid) as istopic
FROM
eZArticle_ArticleCategoryLink acl
WHERE
acl.ArticleID=110147
) as subquery
events