WordPress database error: [Illegal mix of collations for operation ' IN ']
SELECT target.post_id, sum(target.weight * log(19156 / least(19156, freqs.freq))) as score FROM ew_wp_rp_tags as target, (SELECT label, count(1) as freq FROM ew_wp_rp_tags WHERE label IN ('A_alt', 'C_?? ? ????', 'A_a') GROUP BY label ) as freqs WHERE target.post_id NOT IN ('20167') AND target.label=freqs.label AND target.label IN ('A_alt', 'C_?? ? ????', 'A_a') AND target.post_id NOT IN ( SELECT post_id FROM ew_wp_rp_tags WHERE label IN ('C_اجتماع', 'C_اسلایدشو', 'C_افغانستان', 'C_تحلیل', 'C_جهان', 'C_سیاست', 'C_عکس خبری', 'C_گزارش', 'C_منطقه') ) GROUP BY target.post_id ORDER BY score desc, target.post_id desc LIMIT 12;