摘要： 思想：使用左外连接的特性查出左表关联右表（一般右表使用分组查询统计）with n as (select * from base_nrfl nrfl where nrfl.parentid=0) select n.nrflmc, nvl(a.nrflsl,0) as nrflsl,nvl(a.wbj, 阅读全文