基础表创建：
with temp as ( select ‘公司‘ name, ‘1‘ id, ‘‘ pid from dual union all select ‘部门1‘ name , ‘11‘ id, ‘1‘ pid from dual union all select ‘部门2‘ name , ‘12‘ id, ‘1‘ pid from dual union all select ‘员工11‘ name , ‘111‘ id , ‘11‘ pid from dual union all select ‘员工12‘ name , ‘112‘ id , ‘11‘ pid from dual union all select ‘员工21‘ name , ‘121‘ id , ‘12‘ pid from dual )
等号左边的字段为基础，查询右边字段=左边字段的
select * from temp connect by prior id= pid start with id=‘1‘
select * from temp connect by prior id= pid start with id in (‘11‘ ,‘12‘)
添加where语句
select * from temp where id = ‘111‘ connect by prior id= pid start with id in (‘11‘ ,‘12‘)
select * from temp connect by prior pid= id start with id = ‘121‘
connect by prior id= pid start with id='1' 树结构查询
原文：https://www.cnblogs.com/-beauTiFul/p/9121553.html