Illegal mix of collations (cp1251_general_ci,IMPLICIT) and (utf8_general_ci,COERCIBLE) for operation '='
SELECT `ArticleID` FROM SC_articles WHERE `ArticleSlug`='IB_demo_Èññëåäîâàíèå_ðûíêà_ñàíòåõíèêè.Èþëü_2015.pdf'