对于 mysql 表字段的分行处理

select a.id,
substring_index(substring_index(a.cjfq,' ',b.help_topic_id + 1),' ',-1) cjfq
from crawl_data_references a
join mysql.help_topic b
on b.help_topic_id < length(a.cjfq) - length(replace(a.cjfq,' ',''))+1 and a.cjfq !=''