原始数据
处理后
sql
SELECT a.id
, a.NAME
, substring_index(substring_index(a.shareholder, ',', b.help_topic_id + 1), ',', - 1) AS shareholder
FROM company a
INNER JOIN mysql.help_topic b
ON b.help_topic_id < (length(a.shareholder) - length(REPLACE(a.shareholder, ',', '')) + 1)