CONCAT substr group_concat find_in_set

(SELECT p.*,(SELECT CONCAT(m.name,m.id) FROM service_fastfix_category m WHERE m.id=SUBSTR(p.id,1,4)) AS parentcode,(SELECT GROUP_CONCAT(ee.name

)FROM ele_part_category ee  WHERE FIND_IN_SET(ee.code,p.m_part_category_ids))AS groupname FROM service_fastfix_category p ORDER BY p.id) a

 

 

1、substr()字符串截取功能。

2、concat（）连接

SELECT CONCAT(phone,state)AS dd FROM app_user ORDER BY dd

3、FIND_IN_SET(ee.code,p.m_part_category_ids)

找到code在m_part_category_ids的位置

4、group—concat（）

SELECT brandid,GROUP_CONCAT(seriesid) AS ss FROM app_user_car  GROUP BY brandid