Question

I need to get data from third-occurrence position of “*” to 4th. I do so:

    with t as (select 'T*76031*12558*test*received percents' as txt from dual)
         select regexp_replace(txt, '.*(.{4})[*][^*].*$', '\1')
    from t

I receive “test” – it’s right, but how to get any number of characters, not just 4?

Answer 1

This should work given the example you have used:

REGEXP_REPLACE( txt, '(^.*\*.*\*.*\*)([[:alnum:]]*)(\*.*$)', '\2')

So the SELECT would be:

WITH t 
  AS (SELECT 'T*76031*12558*test*received percents' AS txt FROM DUAL)
SELECT REGEXP_REPLACE( txt, '(^.*\*.*\*.*\*)([[:alnum:]]*)(\*.*$)', '\2')
  FROM t;

The regex looks for:

Group 1:
start of string. Any number of characters up to a ‘‘. Any further characters up mto another ‘‘. Any further characters up to the third ‘*’.

Group 2:
Any alphanumeric characters

Group 3:
A ‘*’ followed by any other characters up to the end of the string.

Replace all of the above with whatever was found in Group 2.

Hope this helps.

EDIT:
Following on from a great answer from another thread by Rob van Wijk here:

Exracting substring from given string

WITH t 
  AS (SELECT 'T*76031*12558*test*received percents' AS txt FROM DUAL)
SELECT REGEXP_SUBSTR( txt,'[^\*]+',1,4)
  FROM t;