[8i] Need help with hierarchical (connect by) query

Question

First, I'm working in 8i.
My problem is, I keep getting the error ORA-01437: cannot have join with CONNECT BY.
And, the reason I get that error is because one of the criteria I need to use to prune some branches with is in another table... Is there anyway to work around this? I tried an in-line view (but got the same error). I thought about using the connect by query as an in-line view and filtering off what I don't want that way, but I'm not sure how to filter out an entire branch...
Here is some simplified sample data:
CREATE TABLE     bom_test
(     parent          CHAR(25)
,     component     CHAR(25)
,     qty_per          NUMBER(9,5)
INSERT INTO     bom_test
VALUES     ('ABC-1','101-34',10);
INSERT INTO     bom_test
VALUES     ('ABC-1','A-109-347',2);
INSERT INTO     bom_test
VALUES     ('ABC-1','ABC-100G',1);
INSERT INTO     bom_test
VALUES     ('ABC-1','1A247G01',2);
INSERT INTO     bom_test
VALUES     ('ABC-100G','70052',18);
INSERT INTO     bom_test
VALUES     ('ABC-100G','M9532-278',5);
INSERT INTO     bom_test
VALUES     ('1A247G01','X525-101',2);
INSERT INTO     bom_test
VALUES     ('1A247G01','1062-324',2);
INSERT INTO     bom_test
VALUES     ('X525-101','R245-9010',2);
CREATE TABLE     part_test
(     part_nbr     CHAR(25)
,     part_type     CHAR(1)
INSERT INTO     part_test
VALUES     ('ABC-1','M');
INSERT INTO     part_test
VALUES     ('101-34','P');
INSERT INTO     part_test
VALUES     ('A-109-347','P');
INSERT INTO     part_test
VALUES     ('ABC-100G','M');
INSERT INTO     part_test
VALUES     ('1A247G01','P');
INSERT INTO     part_test
VALUES     ('70052','P');
INSERT INTO     part_test
VALUES     ('M9532-278','P');
INSERT INTO     part_test
VALUES     ('X525-101','M');
INSERT INTO     part_test
VALUES     ('1062-324','P');
INSERT INTO     part_test
VALUES     ('R245-9010','P');This is the basic query (with no pruning of branches):
SELECT     LEVEL
,     b.component
,     b.parent
,     b.qty_per
FROM     bom_test b
START WITH          b.parent     = 'ABC-1'
CONNECT BY PRIOR     b.component     = b.parentThe query above gives the results:
      LEVEL COMPONENT                 PARENT                        QTY_PER
      1.000 101-34                    ABC-1                          10.000
      1.000 A-109-347                 ABC-1                           2.000
      1.000 ABC-100G                  ABC-1                           1.000
      2.000 70052                     ABC-100G                       18.000
      2.000 M9532-278                 ABC-100G                        5.000
      1.000 1A247G01                  ABC-1                           2.000
      2.000 X525-101                  1A247G01                        2.000
      3.000 R245-9010                 X525-101                        2.000
      2.000 1062-324                  1A247G01                        2.000
9 rows selected....but I only want the branches (children, grandchildren, etc.) of part type 'M'.
e.g.:
      LEVEL COMPONENT                 PARENT                        QTY_PER
      1.000 101-34                    ABC-1                          10.000
      1.000 A-109-347                 ABC-1                           2.000
      1.000 ABC-100G                  ABC-1                           1.000
      2.000 70052                     ABC-100G                       18.000
      2.000 M9532-278                 ABC-100G                        5.000
      1.000 1A247G01                  ABC-1                           2.000Any suggestions?

Answer 1

Hi,
user11033437 wrote:
First, I'm working in 8i.
My problem is, I keep getting the error ORA-01437: cannot have join with CONNECT BY.
And, the reason I get that error is because one of the criteria I need to use to prune some branches with is in another table... Is there anyway to work around this? I tried an in-line view (but got the same error). Post your query. It's very hard to tell what you're doing wrong if we don't know what you're doing.
...but I only want the branches (children, grandchildren, etc.) of part type 'M'.
e.g.:
LEVEL COMPONENT                 PARENT                        QTY_PER
1.000 101-34                    ABC-1                          10.000
1.000 A-109-347                 ABC-1                           2.000
1.000 ABC-100G                  ABC-1                           1.000
2.000 70052                     ABC-100G                       18.000
2.000 M9532-278                 ABC-100G                        5.000
1.000 1A247G01                  ABC-1                           2.000
You mean you want don't want the descendants (children, grandchildren, etc.) of any component whose part_type is not 'M'.
The part_type of the component itself doesn't matter: component '101-34' is included, even though its part_type is 'P', and component 'X525-101' is excluded, even though its part_type is 'M'.
>
Any suggestions?Sorry, I don't have an Oracle 8.1 database at hand now. All three of the queries below get the correct results in Oracle 10.2, and I don't believe they do anything that isn't allowed in 8.1.
You can't do a join and CONNECT BY in the same query on Oracle 8.1.
I believe you can do one first, then the other, using in-line views. The frist two queries do the join first.
--     Query 1: Join First
SELECT     LEVEL
,     component
,     parent
,     qty_per
FROM     (     -- Begin in-line view to join bom_test and part_test
          SELECT     b.component
          ,     b.parent
          ,     b.qty_per
          ,     p.part_type     AS parent_type
          FROM     bom_test     b
          ,     part_test     p
          WHERE     p.part_nbr     = b.parent
     )     -- End in-line view to join bom_test and part_test
START WITH     parent     = 'ABC-1'
CONNECT BY     parent          = PRIOR component
     AND     parent_type     = 'M'
;Query 2 is very much like Query 1, but it does more filtering in the sub-query, returning only rows hose part_type or whose parent's part_type is 'M". Your desired result set will be a tree taken entirely from this set. Query 2 may be faster, because the sub-query is more selective, but then again, it may be slower because it has to do an extra join.
{code}
-- Query 2: Join first, prune in sub-query
SELECT     LEVEL
,     component
,     parent
,     qty_per
FROM     (     -- Begin in-line view to join bom_test and part_test
          SELECT     b.component
          ,     b.parent
          ,     b.qty_per
          ,     p.part_type     AS parent_type
          FROM     bom_test     b
          ,     part_test     p
          ,     part_test     c
          WHERE     p.part_nbr     = b.parent
          AND     c.part_nbr     = b.component
          AND     'M'          IN (c.part_type, p.part_type)
     )     -- End in-line view to join bom_test and part_test
START WITH     parent     = 'ABC-1'
CONNECT BY     parent          = PRIOR component
     AND     parent_type     = 'M'
{code}
Query 3, below, takes a completely different approach. It does the CONNECT BY query first, then does a join to see what the parent's part_type is. We can easily cut out all the nodes whose parent's part_type is not 'M', but that will leave components like 'R245-9010' whose parent has part_type 'M', but should be excluded because its parent is excluded. To get the correct results, we can do another CONNECT BY query, using the same START WITH and CONNECT BY conditions, but this time only looking at the pruhed results of the first CONNECT BY query.
{code}
--     Query 3: CONNECT BY, Prune, CONNECT BY again
SELECT     LEVEL
,     component
,     parent
,     qty_per
FROM     (     -- Begin in-line view of 'M' parts in hierarchy
          SELECT     h.component
          ,     h.parent
          ,     h.qty_per
          FROM     (     -- Begin in-line view h, hierarchy from bom_test
                    SELECT     component
                    ,     parent
                    ,     qty_per
                    FROM     bom_test
                    START WITH     parent     = 'ABC-1'
                    CONNECT BY     parent     = PRIOR component
               ) h     -- End in-line view h, hierarchy from bom_test
          ,     part_test     p
          WHERE     p.part_nbr     = h.parent
          AND     p.part_type     = 'M'
     )     -- End in-line view of 'M' parts in hierarchy
START WITH     parent     = 'ABC-1'
CONNECT BY     parent     = PRIOR component
{code}
I suspect that Query 3 will be slower than the others, but if the CONNECT BY query is extremely selective, it may be better.
It would be interesting to see your findings using the full tables. Please post your observations and the explain plan output.
As usual, your message is a model of completeness and clarity:
<ul>
<li>good sample data,
<li> posted in a way people can use it,
<li>clear results,
<li> good explanation
<li> nciely formatted code
</ul>
Keep up the good work!