Re: Boolean Function in SQL

I don't know about any existing function but you can easily create one:

create or replace function is_number(p_argument varchar2) return boolean is l_number NUMBER(10);
begin
  l_number:=to_number(p_argument);
  return TRUE;
exception
  when others
  then
    return FALSE;
end;
/

Now you can test it with the following statement:

  1 begin
  2 if is_number('123')
  3 then
  4 dbms_output.put_line('TRUE');
  5 else
  6 dbms_output.put_line('FALSE');
  7 end if;
  8 if is_number('character')
  9 then
 10 dbms_output.put_line('TRUE');
 11 else
 12 dbms_output.put_line('FALSE');
 13 end if;
 14* end;
SQL> /
TRUE
FALSE PL/SQL procedure successfully completed.

Good luck,

Reinier
<pmohanan_at_my-deja.com> wrote in message news:8rdfue$db2$1_at_nnrp1.deja.com...
> Hi..All,
>
>
> Is there any function in Oracle which returns 1/TRUE or 0/FALSE
> depending on the condition. I am trying to check whether the value of a
> particluar column is numeric.
>
> When i use to_number(col_name,'99999999') it bombs when it received a
> char_value.
>
> Is there any function like isnumber()? or ischar() in oracle.
>
> The alternative i found was
> substr(col_name,1,1) in ('0','1',.....'9')
>
> Any other alternatives?
>
> Regards,
>
> Praveen
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
Received on Wed Oct 04 2000 - 02:54:26 CDT