Adding exception in XML

Question

hi
here is small snippet of my code that generates the XML in oracle
i want to add the exception in the code.
how to do so?
XMLElement("PersonalDetails",     
                         XMLForest(NVL(to_char(to_date(a.DOB,'YYYYMMDD'),'DD-MM-YYYY'),' ') AS "DOB",
                              NVL(a.Gender,' ') AS "Gender",
                              NVL(a.MaidenName,' ') AS "MaidenName")))
if the format of date is wrong, it throws the exception. i want to catch the exception here itself.

Answer 1

How many different formats are there stored in the string?
ddmmyyyy
mmddyyyy
ddmmyy
mmddyy
dd/mm/yyyy
dd/mm/yy
mm/dd/yyyy
mm/dd/yy
dd-mm-yyyy
dd-mm-yy
mm-dd-yyyy
mm-dd-yyyy
yyyymmdd
yymmdd
yyyyddmm
yyddmm
etc.
You're going to have to string process to determine which one the string matches using CASE and then apply the correct to_date format mask for that format.
e.g.
SQL> ed
Wrote file afiedt.buf
  1  with t as (select '01012008' as dt from dual union all
  2             select '130208' from dual union all
  3             select '12/02/2008' from dual union all
  4             select '12-02/2008' from dual union all
  5             select 'a2-02/2008' from dual union all
  6             select '01-04-08' from dual)
  7  -- end of test data
  8  select dt, case when regexp_like(dt, '^[[:digit:]\/-]*$') then
  9                  -- all numbers or numbers with seperators
10                  case when regexp_like(dt, '^[[:digit:]]*$') and length(dt) = 8 then
11                            to_char(to_date(dt,'ddmmrrrr'),'yyyymmdd')
12                       when regexp_like(dt, '^[[:digit:]]*$') and length(dt) = 6 then
13                            to_char(to_date(dt,'ddmmrr'),'yyyymmdd')
14                       when regexp_like(dt, '^[[:digit:]\/]*$') and length(dt) = 10 then
15                            to_char(to_date(dt,'dd/mm/rrrr'),'yyyymmdd')
16                       when regexp_like(dt, '^[[:digit:]\/]*$') and length(dt) = 8 then
17                            to_char(to_date(dt,'dd/mm/rr'),'yyyymmdd')
18                       when regexp_like(dt, '^[[:digit:]-]*$') and length(dt) = 10 then
19                            to_char(to_date(dt,'dd-mm-rrrr'),'yyyymmdd')
20                       when regexp_like(dt, '^[[:digit:]-]*$') and length(dt) = 8 then
21                            to_char(to_date(dt,'dd-mm-rr'),'yyyymmdd')
22                  else
23                    'unknown format'
24                  end
25             else
26               'invalid date'
27             end as formatted_date
28* from t
SQL> /
DT         FORMATTED_DATE
01012008   20080101
130208     20080213
12/02/2008 20080212
12-02/2008 unknown format
a2-02/2008 invalid date
01-04-08   20080401
6 rows selected.
SQL>Message was edited by:
BluShadow
correction to lengths