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Question

Please can someone help
see below example
My aim is to find the top parent node but pass in a lower or joint level item.
So my example here has contains the tree structure
100 'A'
200 'B'
300 'B'
And i require if i put in 300 'B' or 200 'B' it tells me 100 'A' is top of the tree.
I thought the code i did would work but this gives me the wrong level as to what i believe should be top so i am obviousely doing something wrong
level         parent        child
1              300           400
2              200           300
3              100           200but the top level is parent 100 code A should this not be 1 not 3??
This was my query can someone please tell me what im doing wong.
It uses a number and a code to link. so it needs both code and number parent to be correct for link as you could potentially have
parent 100 code A
or
parent 100 code B
And these are two completely different items.
select level, parent,child
from
select 100 as parent,'A' as parentcode,200 as child, 'B' as childcode from dual
union
select 200 as parent,'B' as parentcode,300 as child, 'B' as childcode from dual
union
select 300 as parent,'B' as parentcode,400 as child, 'B' as childcode from dual
connect by child=prior parent and childcode=prior parentcode
start with child=400 and childcode ='B'Edited by: guest1111111 on May 11, 2009 4:16 PM

Answer 1

The first query I gave you does just that:
SQL> ed
Wrote file afiedt.buf
  1  WITH testdata as (select 100 as parent,'A' as parentcode,200 as child, 'B' as childcode from dual union all
  2                    select 200 as parent,'B' as parentcode,300 as child, 'B' as childcode from dual union all
  3                    select 300 as parent,'B' as parentcode,400 as child, 'B' as childcode from dual
  4                   )
  5  select level, parent, child
  6  from testdata
  7  where connect_by_isleaf = 1
  8  connect by child = prior parent and childcode = prior parentcode
  9* start with child=&child and childcode ='&childcode'
SQL> /
Enter value for child: 400
Enter value for childcode: B
old   9: start with child=&child and childcode ='&childcode'
new   9: start with child=400 and childcode ='B'
     LEVEL     PARENT      CHILD
         3        100        200
SQL> /
Enter value for child: 300
Enter value for childcode: B
old   9: start with child=&child and childcode ='&childcode'
new   9: start with child=300 and childcode ='B'
     LEVEL     PARENT      CHILD
         2        100        200
SQL> /
Enter value for child: 200
Enter value for childcode: B
old   9: start with child=&child and childcode ='&childcode'
new   9: start with child=200 and childcode ='B'
     LEVEL     PARENT      CHILD
         1        100        200
SQL>The only thing that changes is the "level" because that is how 'deep' it's had to go to get to the result.