Fatal error: Uncaught Exception: DB Error: Illegal mix of collations (utf8mb3_unicode_ci,IMPLICIT) and (utf8mb3_general_ci,IMPLICIT) for operation '=' Query: SELECT o.submission_id, MAX(s.context_id) AS journal_id, MAX(i.date_published) AS i_pub, MAX(p.date_published) AS s_pub, COUNT(*) AS count FROM submissions s JOIN publications p ON (p.publication_id = s.current_publication_id) JOIN publication_settings ps ON (ps.publication_id = p.publication_id AND ps.setting_name='issueId') JOIN issues i ON (CAST(i.issue_id AS CHAR(20)) = ps.setting_value) JOIN submission_search_objects o ON (s.submission_id = o.submission_id) NATURAL JOIN submission_search_object_keywords o0 NATURAL JOIN submission_search_keyword_list k0 WHERE s.status = 3 AND i.published = 1 AND k0.keyword_text = ? AND i.journal_id = ? GROUP BY o.submission_id ORDER BY count DESC LIMIT 500 in /var/www/html/lib/pkp/classes/db/DAO.inc.php:703 Stack trace: #0 /var/www/html/lib/pkp/classes/db/DAO.inc. in /var/www/html/lib/pkp/classes/db/DAO.inc.php on line 703