I had a mysql query where i need to add some condition in Group by statement , if i use single field in Group by it works but i need two field include in the Group by, here is my query any one please help me to find out the issue
SELECT (CASE
WHEN CSR.skill_type = 1 THEN
(SELECT skills_value from cv_skills
WHERE skills_id = CSR.skill_id )
WHEN CSR.skill_type = 2 THEN
(SELECT ostype_name from cv_os_type
WHERE ostype_id = CSR.skill_id )
WHEN CSR.skill_type = 3 THEN
(SELECT dbtype_name from cv_db_type
WHERE dbtype_id = CSR.skill_id)
WHEN CSR.skill_type = 4 THEN
(SELECT title from candidate_competencies
WHERE id = CSR.skill_id)
WHEN CSR.skill_type = 0 THEN
IT.type_name
END) AS skill_name,
(CASE
WHEN IT.type_parent_id > 0 THEN
IT.type_parent_id
WHEN IT.type_parent_id = 0 THEN
CIS.interview_type
END) AS typeId,
(CASE
WHEN CSR.skill_type = 4 THEN
minimum_rating
END) AS minimum_rating,
AVG( CSR.rate ) AS skill_rating,
CSR.skill_type,CIS.created, CC.id
FROM `candidate_interview_skill_rate` `CSR`
LEFT JOIN `candidate_interview_process` `CIP` ON CSR.interview_process_id = CIP.id
LEFT JOIN `candidate_interview_schedule` `CIS` ON CIS.id = CIP.interview_schedules_id AND CIS.archive_date IS NULL
LEFT JOIN `candidate_interview` `CI` ON CI.id = CIS.interview_id AND CI.archived_date IS NULL
LEFT JOIN `interview_type` `IT` ON IT.id = CIS.interview_type
LEFT JOIN `candidate_competencies` `CC` ON CC.id = CSR.skill_id
WHERE CI.candidate_user_id = 39
GROUP BY (CASE
WHEN CSR.skill_type > 0 THEN
CSR.skill_id, CSR.skill_type
ELSE CIS.interview_type
END)
ORDER BY `CSR`.`skill_type`