INSERT INTO query_cache(session_id, url_id, weight)    SELECT DISTINCT 't4qa4ch7e0s365pi5f4b4ouv21',u.id,1 as weight
                                  FROM lect_url AS u
                                  WHERE (LOCATE('', u.author )>0)
                                    AND u.is_visible=1  
Illegal mix of collations (utf8mb4_general_ci,IMPLICIT) and (utf8mb3_general_ci,COERCIBLE) for operation 'locate'

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