Schedule for KWDS

Deadline for Class Submissions: 0

Error is query: SELECT DISTINCT as id,, CONCAT(COALESCE(U1.sca_first,''),' ', COALESCE(U1.sca_last,''),' [',COALESCE(U1.first,''),' ',COALESCE(U1.last,''),']') as user_id,, ADDTIME(, SEC_TO_TIME(C1.hours*60)) as end FROM class C1 INNER JOIN coteacher T1 ON T1.class_id = LEFT OUTER JOIN user U1 ON = T1.user_id INNER JOIN class C2 ON != INNER JOIN coteacher T2 ON = T2.class_id AND T1.user_id = T2.user_id WHERE C1.kwds_ID = AND C2.kwds_ID = AND (( >= AND < ADDTIME(, SEC_TO_TIME(C2.hours*60))) OR ((ADDTIME(, SEC_TO_TIME(C1.hours*60)) > AND ADDTIME(, SEC_TO_TIME(C1.hours*60)) <= ADDTIME(, SEC_TO_TIME(C2.hours*60))))) ORDER BY T1.user_id,