Find a number in a string

Question

Hi all,
I've got a text field in my source table that can contain both numbers and characters, like any normal varchar2. The issue is with a field that should contain insurance numbers, but also thinks "hello world" will do! A change to the application will not help, nor any constraints on database level will do!
I want to determine if a record has any numbers, if it has, than i validate it to ok, if not, so only characters are in the field, than i want to validate it to not ok.
My solution so far is that I use a case statement with a translate, which translates all characters to a zero and leaves numbers untouched. When result is larger than zero it is valid
So 'ABC123 ' would return 0001230 and evaluate to true, even so '0 123 ABC' would translate 001230000 and will also evaluate to true, and ABC will evaluate to false, exactly how I like it to be.
But...the translate function has all charaters that are directly visible on my keyboard, in upper and lower case, and now i bumped into a special character. An E with two dots above (alt 137).
now to prevent me from building a solution that has all the characters in it which I could ever produce in my translate is there any smarter sollution?
Hope you guys (or girls) can help!
Cheers,
Gilles

Answer 1

Gilles,
What you need is a regular expression. Below is a simple example using the Oracle regexp_like function to determine if the function's input has any numeric characters in it, and returns 1 if it does, otherwise it returns 0:
create or replace function find_digit(p_string varchar2) return number is
l_ret boolean;
begin
l_ret := regexp_like(p_string, '[[:digit:]]');
if l_ret then return 1; else return 0; end if;
end;
You should be able to use something like this. you can use the regexp_like function in the WHERE clause of your SQL or wrap it in to a function like this you need it in the SELECT clause (as the return type of regexp_like is boolean which isn't supported in the SELECT clause).
hope this helps,
Borkur