Oracle递归查询 Start with…Connect By用法

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oracle中的select语句可以用START WITH…CONNECT BY PRIOR子句实现递归查询，其基本语法如下：

select … from <TableName>
where <Conditional-1>
start with <Conditional-2>
connect by <Conditional-3>

<Conditional-1>：过滤条件，用于对返回的所有记录进行过滤。

<Conditional-2>：查询结果重起始根结点的限定条件，种子号，整形字符串都可以，只要有增长规则。

<Conditional-3>：连接条件，父子id关系

从Root往树末梢递归

select * from TBL_TEST
start with id=1
connect by prior id = parentId

从末梢往树ROOT递归

select * from TBL_TEST
start with id=5
connect by prior pid = id