分类: Oracle
2008-05-23 13:37:32
来源: |
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Start with...Connect By子句递归一般用于一个表维护树形结构的应用。
创建示例表:
CREATE TABLE TBL_TEST
( ID NUMBER, NAME VARCHAR2(100 BYTE), PID NUMBER DEFAULT 0 ); 插入测试数据:
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'); 从Root往树末梢递归
select * from TBL_TEST
start with id=1 connect by prior id = pid 从末梢往树ROOT递归
select * from TBL_TEST start with id=5 connect by prior pid = id |