Best way to solve ORA-01722: invalid number

Question

Hi,
I recently had to debug a large Merge statement that was getting 'ORA-01722: invalid number' and I found the only way to do it was comment out the columns until I found the culprit :-(
Surely in this day and age there is a better way to do this? Oracle knows which column fails so it there a way of finding it more quickly?
We are using Oracle 9.2
Thanks for any top tips
Regards
Gary

Answer 1

you can do a cursor and trap the exception
create table t1 as select '1' col1, '2' col2 from dual union all select '1','x' from dual union all select 'x','2' from dual union all select 'x','x' from dual;
declare
  cursor c1 is select rowid,col1,col2 from t1;
  dummy number;
begin
  for r1 in c1 loop
    begin
      select to_number(r1.col1) into dummy from dual;
    exception
      when INVALID_NUMBER then
        dbms_output.put_line(r1.rowid||' col1='||r1.col1);
      end;
    begin
      select to_number(r1.col2) into dummy from dual;
    exception
      when INVALID_NUMBER then
        dbms_output.put_line(r1.rowid||' col2='||r1.col2);
    end;
  end loop;
end;
AAAKGCAAEAAAAECAAB col2=x
AAAKGCAAEAAAAECAAC col1=x
AAAKGCAAEAAAAECAAD col1=x
AAAKGCAAEAAAAECAAD col2=xHTH
Laurent Schneider
OCM DBA