1. 得到两张表中 area_code = region_code 的独特 region_code 字段 (两种写法)
(1) select distinct area.region_code from TB_ORGANIZATION org inner join TB_ADMINDIVISION area on (org.area_code=area.region_code)
(2) select distinct area.region_code from TB_ORGANIZATION org , TB_ADMINDIVISION area where org.area_code=area.region_code
2.oracle 树形结构 ,由子节点递归得到父节点
比如有一个表:
guid parentguid
1 0
2 1
3 1
4 2
5 2
6 5
7 5
8 7
我们从GUID为1根据parentguid关系可以查出该GUID下的所有子节点.
现在要从某一子节点如GUID为7,查出它的父节点, 7->5->2->1的关系.
select guid from test start with guid =7 connect by prior parentguid = guid
即可以查出7->5->2->1的关系
test 为表名 guid 为 id parentguid 为 pid
实例:
select region_code,area_name,parentcode from TB_ADMINDIVISION start with region_code in (
select distinct area.region_code from TB_ORGANIZATION org inner join TB_ADMINDIVISION area on (org.area_code=area.region_code)
) connect by prior parentcode=region_code