题解 | #修复串列了的记录#
修复串列了的记录
https://www.nowcoder.com/practice/a5475ed3b5ab4de58e2ea426b4b2db76
select
exam_id,
substring_index (tag, ',', 1) as tag,
substring_index (substring_index (tag, ',', -2), ',', 1) as difficulty,
substring_index (tag, ',', -1) as duration
from
examination_info
where
tag like '%,%'
