Oracle实现递归查询

有如下表Tree:

Oracle实现递归查询_第1张图片

现在要递归查询冶炼(id=2)的所有父节点和子节点:

SELECT * FROM tree START WITH id = 2 CONNECT BY PRIOR pid = id -- 递归查询父节点
union
SELECT * FROM tree START WITH id = 2 CONNECT BY pid = PRIOR id; -- 递归查询子节点
查询结果:


当然,也可以使用in关键字递归查询多个节点的父节点和子节点:

SELECT * FROM tree START WITH id in (1, 10) CONNECT BY PRIOR pid = id -- 递归查询父节点
union
SELECT * FROM tree START WITH id in (1, 10) CONNECT BY pid = PRIOR id; -- 递归查询子节点
以上语句递归查询id为1或者10的父节点和子节点,结果如下:

Oracle实现递归查询_第2张图片



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