user871695 user871695 - 2 months ago 15
SQL Question

START WITH and CONNECT BY in Oracle SQL

I have table as below

ACCOUNT

CUSTOMER_ID PAYING_ACCOUNT_ID PARENT_ACCOUNT_ID ACCOUNT_ID COMPANY_ID
24669 24669 24669 24669 0
24671 24671 24669 24671 0
24670 24670 24669 24670 0
3385217 3385217 24670 3385217 0
158 158 158 158 0
159 159 158 159 0
160 160 159 160 0
161 161 160 161 0
162 162 160 162 0
180 180 180 180 0


This is the DDL

CREATE TABLE "SYSTEM"."ACCOUNT"
("CUSTOMER_ID" NUMBER(20,0) NOT NULL ENABLE,
"PAYING_ACCOUNT_ID" NUMBER(20,0),
"PARENT_ACCOUNT_ID" NUMBER(20,0),
"ACCOUNT_ID" NUMBER,
"COMPANY_ID" NUMBER)


This is my query

select lpad(' ', 2*level) || A.ACCOUNT_ID AS LEVEL_LABEL,
LEVEL,
A.*
from ACCOUNT A
start with PARENT_ACCOUNT_ID IN
(select PARENT_ACCOUNT_ID
from ACCOUNT
where ACCOUNT_ID IN
(select PARENT_ACCOUNT_ID
from ACCOUNT
where parent_account_id != account_id)
and ACCOUNT_ID = PARENT_ACCOUNT_ID)
CONNECT BY NOCYCLE PRIOR A.ACCOUNT_ID = A.PARENT_ACCOUNT_ID;


The main objective of the query is to select data that has a hierarchical relationship, which are PARENT_ACCOUNT_ID & ACCOUNT_ID, however i got a duplicate data returned by the query

Any advice much appreciated. Thanks

Answer Source

Why not simply:

 SELECT level, * FROM accounts
 START WITH parent_account_id = account_id
 CONNECT BY PRIOR account_id = parent_account_id
         AND account_id <> parent_account_id

?