oracle递归查询，根据父级节点查询子级节点，遍历树

1.向上递归 

SELECT *
FROM org_group
START WITH PARENT_UUID = '-1'
CONNECT BY PRIOR PARENT_UUID = group_uuid

2,。带有级别的查询

SELECT level ,sys_connect_by_path (group_name, '-->') ,t.*
FROM org_group2 t
START WITH PARENT_UUID = '-1'
CONNECT BY PRIOR PARENT_UUID = t.group_uuid