一、CREATE TABLE TBL_TEST
  (
  ID    NUMBER,
  NAME  VARCHAR2(100 BYTE),
  PID   NUMBER                                  DEFAULT 0
  )
  INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('1','10','0');
  INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('2','11','1');
  INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('3','20','0');
  INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('4','12','1');
  INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('5','121','2');
二、格式
        Select * from …. Where [结果过滤条件语句]
  Start with  [and起始条件过滤语句]
  Connect by prior [and中间记录过滤条件语句]
三、查找所有下级
        select * from tbl_test start with id=1 connect by prior id=pid
  注意:此sql能查找id=1的数据的所有下级,写sql语句时要注意,因为是从id开始查找下级,所以connect by prior 子句的条件是         id=pid
四、查找所有上级
       select * from tbl_test start with id=5 connect by prior pid=id
  因为是从id开始查找上级,所以connect by prior 子句的条件是pid=d

 

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例子: 物资大类

select *
  from ep_goods_cate epgc
 start with epgc.epgc_id in (3,12,115,6)
connect by prior epgc.epgc_id = epgc.epgc_parent_id