SQL 连接多行

Question

是否可以为表中的许多行生成“连接方式”并对它们进行求和。 我有一张桌子

person boss
---------------    
person1 NULL
person2 person1
person3 person2

，我想要得到一张桌子，

boss is_boss_of
---------------
person1 person2
person1 person3
person2 person3

我想通过表达式为桌子上的每个人建立连接？ 有什么办法可以做到吗？

说到总和，我想到了这样的事情

SELECT CONNECT_BY_ROOT person as boss, person as is_boss_of
            FROM table1
            START WITH boss = person1
            CONNECT BY PRIOR Empno = Mgr;
Union
SELECT CONNECT_BY_ROOT person as boss, person as is_boss_of
            FROM table1
            START WITH boss = person2
            CONNECT BY PRIOR Empno = Mgr;
Union
...
and so on

Answer 1

更新

看到更新后，您只需删除“开始”即可。

结束更新

CONNECT_BY_ROOT< /a> 是您要查找的内容

此语句

SELECT distinct RootBoss, Person FROM (
with employee  as 
(
  Select 1 person , null boss from Dual
  UNION Select 2 , 1 from dual
  UNION Select 3 , 2 from dual
)
SELECT CONNECT_BY_ROOT boss RootBoss, person
FROM employee connect_by

  connect by prior person = boss
  ORDER BY person

  ) t
WHERE ROOTBOSS is not null
ORDER BY
RootBoss, Person

输出

ROOTBOSS               PERSON                 
---------------------- ---------------------- 
1                      2                      
1                      3                      
2                      3        

添加 SUMS 和 GROUPS 非常简单