Sql 分层查询，帐户树

我一直使用分层查询来搜索父帐户或子帐户，通常让我们假设一个示例：

表帐户：

Account    Parent
217518     217518 or null
304229     217518
424590     217518
378327     217518
491504     378327
234123     491504

因此，层次结构看起来：

现在，我得到了表“SHOW\u PARENT\u CHILD\u ACC”，我将在其中插入我想要显示的帐户。（我需要在分层查询中使用它）

插入“显示父项子项acc（acc）”值（304229）

查询应返回所有帐户id，以便：

304229     
424590     
378327 
217518    
491504     
234123     

304229     
424590     
378327 
217518    
491504     
234123  

我也会的 插入显示父项cild acc（acc）值（234123）

查询应返回所有帐户id，以便：

304229     
424590     
378327 
217518    
491504     
234123     

304229     
424590     
378327 
217518    
491504     
234123  

换句话说，无论我将哪个帐户（父/子帐户或子帐户的子帐户）插入到show\u parent\u child\u acc表中。查询应返回整个帐户层次结构

现在，我有smth，比如：

WITH acc_to_delete( ID ) AS (
                            select case when parentaccount is null then accountid else parentaccount end from account where accountid in                                          
                                 (select acc from show_parent_child_acc) 
                          )
                          SELECT accountid id_acc,case when parentaccount is null then accountid else parentaccount end parentaccount
                          FROM   account p
                          START WITH
                           EXISTS( SELECT 'X'
                                    FROM   acc_to_delete w
                                    WHERE  p.accountid = w.ID
                                    )
                          CONNECT BY accountid = PRIOR parentaccount
                          union
                          SELECT accountid id_acc,case when parentaccount is null then accountid else parentaccount end parentaccount
                          FROM   account p
                          START WITH
                          EXISTS( SELECT 'X'
                                    FROM   acc_to_delete w
                                    WHERE  p.accountid = w.ID
                                    )
                          CONNECT BY PRIOR accountid = parentaccount 
                      

---

但它并没有像预期的那样工作（在我放入SHOW\u PARENT\u CHILD\u ACC:217518..时工作正常）

我将从查找根id（子查询“root”）开始，然后创建典型的层次结构：

with 
  tmp as (select acc from show_parent_child_acc ),
  root as (
    select max(acnt) keep (dense_rank last order by lvl) root
      from (
        select nvl(parentaccount, accountid) acnt, level lvl  
          from account a cross join tmp
          connect by nocycle prior parentaccount = accountid
          start with accountid = acc or parentaccount = acc ))
select accountid from account cross join root
  connect by nocycle prior accountid = parentaccount
  start with parentaccount = root.root
union select root from root

测试数据和输出：

create table account (accountid number(8), parentaccount number(8));
insert into account values (217518, 217518);
insert into account values (304229, 217518);
insert into account values (424590, 217518);
insert into account values (378327, 217518);
insert into account values (491504, 378327);
insert into account values (234123, 491504);
create table show_parent_child_acc (acc number(8));
insert into show_parent_child_acc values (234123);

AccountID
---------
   217518
   234123
   304229
   378327
   424590
   491504

---

进一步修改原始查询，如下所示

WITH acc_to_delete( ID ) AS (
                        select case when parentaccount is null then accountid else parentaccount end from account where accountid in                                          
                             (select acc from show_parent_child_acc) 
                      )                      
SELECT DISTINCT accountid id_acc, case when parentaccount is null then accountid else parentaccount end parentaccount 
FROM account START WITH parentaccount in
(                          
    SELECT case when parentaccount is null then accountid else parentaccount end parentaccount
    FROM   account p 
    START WITH
    EXISTS( SELECT 'X'
            FROM   acc_to_delete w
            WHERE  p.accountid = w.ID
        )
    CONNECT BY nocycle accountid = PRIOR parentaccount 
    UNION
    SELECT case when parentaccount is null then accountid else parentaccount end parentaccount
    FROM   account p 
    START WITH
    EXISTS( SELECT 'X'
            FROM   acc_to_delete w
            WHERE  p.accountid = w.ID
            )
    CONNECT BY nocycle PRIOR accountid =  parentaccount
) 
CONNECT BY NOCYCLE parentaccount = PRIOR accountid

---

它主要收集所有相应的家长，然后找到他们的孩子。

很高兴我能帮忙。这里的问题是根值没有明确定义。在您的示例中，217518根本不存在，或者与id具有相同的父项，或者父项为null。我试图编写处理所有情况的查询，这就是出现

nocycle

的原因。我向fajnie pomóc rodakowi，pozdrawiam；-）