题解 | #话题的分布情况#

SELECT 
     SUBSTRING_INDEX(subject_set, ',', 1) subject_id1,COUNT(1) cnt
FROM comment_detail WHERE SUBSTRING_INDEX(SUBSTRING_INDEX(subject_set, ',', 2),',',-1) = '1002'
GROUP BY SUBSTRING_INDEX(subject_set, ',', 1)
ORDER BY SUBSTRING_INDEX(subject_set, ',', 1);