sqlserver 如何递归查询层级数据将父级字段和本级某个字段合并
select stuff((
select '--'+subjectname
from cte_child order by subjectid desc for xml path('')),1,0,'') as subjectname ;
select stuff((
select '--'+subjectname
from cte_child order by subjectid desc for xml path('')),1,0,'') as subjectname ;