Divide a string in order to get the distinct list level.

Question

Hi,
I want to divide a string in order to get the distinct list level to relate this with a category table.
The size of my list is dynamic and because of this I’m unable to find a way to do this!
Here goes an example of what I need to do:
Consider the following list:
Category                Category_ID
Age                     1
Less than 3 months      1.1
Less than 9 months      1.2
Less than 1 year        1.3
Risk                    2
Danger                  2.1
High                    2.1.1
medium                  2.1.2
low                     2.1.3
If I have a row that has category_id "2.1.3" I want to present values as:
"Risk.Danger.Low"
If I have a row that has category_id "1.1" I want to present values as:
"Age.Less than 3 months"Any hint on what I should search in order to accomplish this?
This will be used to produce a report. This report will contain a few thousand rows and the categories will be around 100.
Thanks,
Ricardo

Answer 1

Hello
I think this is a job for sys_connect_by_path....
with p as
(   select 'Age'             descr  ,'1' cat from dual union all
   select 'Less than 3 months'      ,'1.1' cat from dual UNION ALL
   select 'Less than 9 months'      ,'1.2' cat from dual union all
   select 'Less than 1 year'        ,'1.3' cat from dual union all
   select 'Risk'                    ,'2' cat from dual union all
   select 'Danger'                  ,'2.1' cat from dual union all
   select 'High'                    ,'2.1.1' cat from dual union all
   select 'medium'                  ,'2.1.2' cat from dual union all
   select 'low'                     ,'2.1.3' cat from dual
SELECT
    cat,
    LTRIM(SYS_CONNECT_BY_PATH(descr,'.'),'.') route
FROM
        SELECT
            descr,
            cat,
            SUBSTR(cat,1,INSTR(cat,'.',-1)-1) parent
        FROM
            p
START WITH
    parent IS NULL
CONNECT BY
    PRIOR cat = parent
SQL> with p as
  2  (   select 'Age'             descr  ,'1' cat from dual union all
  3     select 'Less than 3 months'      ,'1.1' cat from dual UNION ALL
  4     select 'Less than 9 months'      ,'1.2' cat from dual union all
  5     select 'Less than 1 year'        ,'1.3' cat from dual union all
  6     select 'Risk'                    ,'2' cat from dual union all
  7     select 'Danger'                  ,'2.1' cat from dual union all
  8     select 'High'                    ,'2.1.1' cat from dual union all
  9     select 'medium'                  ,'2.1.2' cat from dual union all
10     select 'low'                     ,'2.1.3' cat from dual
11  )
12  SELECT
13      cat,
14      LTRIM(SYS_CONNECT_BY_PATH(descr,'.'),'.') route
15  FROM
16      (
17          SELECT
18              descr,
19              cat,
20              SUBSTR(cat,1,INSTR(cat,'.',-1)-1) parent
21          FROM
22              p
23      )
24  START WITH
25      parent IS NULL
26  CONNECT BY
27      PRIOR cat = parent
28  /
CAT   ROUTE
1     Age
1.1   Age.Less than 3 months
1.2   Age.Less than 9 months
1.3   Age.Less than 1 year
2     Risk
2.1   Risk.Danger
2.1.1 Risk.Danger.High
2.1.2 Risk.Danger.medium
2.1.3 Risk.Danger.lowHTH
David
Edited by: Bravid on Sep 2, 2011 2:50 PM