Find out if a string contains only ASCII characters

Question

I need to know whether a string contains only ASCII characters. So far I use this REGEX:

DECLARE
    str VARCHAR2(100) := \'xyz\';
BEGIN
    IF REGEXP_LIKE(s         


        

Answer 1

You can use TRANSLATE to do this. Basically, translate away all the ASCII printable characters (there aren't that many of them) and see what you have left.

Here is a query that does it:

WITH input ( p_string_to_test) AS ( 
SELECT 'This this string' FROM DUAL UNION ALL
SELECT 'Test this ' || CHR(7) || ' string too!' FROM DUAL UNION ALL
SELECT 'xxx' FROM DUAL)
SELECT p_string_to_test, 
       case when translate(p_string_to_test, 
       chr(0) || q'[ !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~]', 
       chr(0)) is null then 'Yes' else 'No' END is_ascii
FROM input;

+-------------------------+----------+
|    P_STRING_TO_TEST     | IS_ASCII |
+-------------------------+----------+
| This this string        | Yes      |
| Test this  string too!  | No       |
| xxx                     | Yes      |
+-------------------------+----------+