循环查询问题
source depend depend_filename 
IM200908210099 PM200908260001 rootcause
IM200908210099 PM200908260002 cm3t
IM200908210099 PM200908260003 rootcause
IM200908210099 PM200908260004 cm3t

表名为a

首先有一个编号IM200906250048,根据这个编号查询select source,depend,depend_filename from a where source='IM200906250048',
然后再把查询出来的depend当作SOURCE继续查select source,depend,depend_filename from a where source='PM200908260001',
然后再将查询出来的depend再作为source继续查询，就这样一直循环下去，直到查询出来的depend没有数据为止，请问一下大家该怎么处理呢？





------解决方案--------------------
参考：
SELECT * from a
WHERE depend is not null
connect by prior depend=source start with source='IM200906250048'