Oracle中的简单递归查询 [英] Simple recursive query in Oracle

问题描述

我目前在理解和编写递归查询时遇到一些麻烦.我知道递归查询用于搜索信息层次结构，但是我还没有找到一个可以遍历层次结构的简单在线解决方案.例如，假设我有一个对家谱建模的关系:

I'm currently having some trouble understanding and writing recursive queries. I understand that recursive queries are used to search through hierarchies of information, but I haven't found a simple solution online that can travel up a hierarchy. For example, let's say that I have a relation that models a family tree:

create table family_tree (
child varchar(10)
parent varchar(10)
);

如果我想编写一个遍历此家谱的递归查询，收集所有父母直到出身，我应该怎么做?

If I wanted to write a recursive query that travelled up this family tree, collecting all parents until origin, how should I go about this?

谢谢.

推荐答案

您可以使用connect by子句.

在您的情况下，SQL可能类似于:

In your case, SQL might look like:

select child, parent, level
from family_tree 
connect by prior parent = child

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