MYSQL擷取列裡面的資料為多行
阿新 • • 發佈：2019-01-16
/**單選統計**/
SELECT syyou,count(syyou) from test_form_one group BY syyou/**複選統計**/
select substring_index(substring_index(a.race,'|',b.help_topic_id+1),'|',-1) as race,count(substring_index(substring_index(a.race,'|',b.help_topic_id+1),'|',-1))
from test_form_one a
join mysql.help_topic b
on b.help_topic_id < (length(a.race) - length(replace(a.race,'|',''))+1)
group BY substring_index(substring_index(a.race,'|',b.help_topic_id+1),'|',-1)
order by a.id;
擷取的核心語句為：
select substring_index(substring_index(a.race,'|',b.help_topic_id+1),'|',-1) from test_form_one a
join mysql.help_topic b
on b.help_topic_id < (length(a.race) - length(replace(a.race,'|',''))+1)
order by a.id;
參考的檔案地址：http://www.cnblogs.com/cenalulu/archive/2012/08/20/2647463.html