Oracle SQL query to find special characters for phone numbers

Question

I am trying to write a query to find special character for phone numbers.

Expected phone number is: 2047653894

Actual: 204765389(4 , 204-7653894 , -2047653894 , (204)7653894 , 20476+53894 , ....

NOTE: I only want to find the phone numbers with special characters. I don't want to replace special characters.

Answer 1

Another option is to remove all non-digits (here, where I live, phone numbers are digits only ; I'm not talking about various formats phone numbers might have):

SQL> with test (col) as
  2    (select '204765389(4'  from dual union all
  3     select '204-7653894'  from dual union all
  4     select '-2047653894'  from dual union all
  5     select '(204)7653894' from dual union all
  6     select '20476+53894'  from dual
  7    )
  8  select
  9    col,
 10    regexp_replace(col, '\D') result
 11  from test;

COL          RESULT
------------ ------------------------------------------------
204765389(4  2047653894
204-7653894  2047653894
-2047653894  2047653894
(204)7653894 2047653894
20476+53894  2047653894

SQL>

---

[EDIT]

If you just want to find phone numbers that contain anything but digits, use regexp_like :

SQL> with test (col) as
  2    (select '204765389(4'  from dual union all
  3     select '204-7653894'  from dual union all
  4     select '-2047653894'  from dual union all
  5     select '(204)7653894' from dual union all
  6     select '20476+53894'  from dual union all
  7     select '2047653897'   from dual
  8    )
  9  select col
 10  from test
 11  where regexp_like(col, '\D');

COL
------------
204765389(4
204-7653894
-2047653894
(204)7653894
20476+53894

SQL>

Answer 2

You can use [[:punct:]] posix along with REGEXP_REPLACE() such as

SELECT REGEXP_REPLACE(col,'[[:punct:]]') AS col
  FROM t

assuming each comma-separated value represents a column value within a table

Demo

Answer 3

While you can use regular expressions, they are slow and it may be faster to use simple string functions and use TRANSLATE to find all the non-numeric characters and then replace them:

SELECT TRANSLATE(
         phone_number,
         '0' || TRANSLATE(phone_number, 'x0123456789', 'x')
         '0'
       ) AS simplified_phone_number
FROM   table_name;

Which, for your sample data:

CREATE TABLE table_name (phone_number) AS
  SELECT '204765389(4' FROM DUAL UNION ALL
  SELECT '204-7653894' FROM DUAL UNION ALL
  SELECT '-2047653894' FROM DUAL UNION ALL
  SELECT '(204)7653894' FROM DUAL UNION ALL
  SELECT '20476+53894' FROM DUAL;

Outputs:

SIMPLIFIED_PHONE_NUMBER
2047653894
2047653894
2047653894
2047653894
2047653894

fiddle

---

Update

If you want to list phone numbers with non-digit characters then you can also use TRANSLATE to remove the digits and check if there are any other characters:

SELECT *
FROM   table_name
WHERE  TRANSLATE(phone_number, 'x0123456789', 'x') IS NOT NULL

you could also use REGEXP_LIKE to check that the string is not entirely digits:

SELECT *
FROM   table_name
WHERE  NOT REGEXP_LIKE(phone_number, '^\d+$')

or that there are non-digits:

SELECT *
FROM   table_name
WHERE  REGEXP_LIKE(phone_number, '\D')

However, regular expressions are probably going to be slower than simple string functions like TRANSLATE .

fiddle