SQL & PL/SQL

Not sure about a clean regular expression for it. I'm sure CD will be along soon to show us how... in the meantime, I managed to get it to deal with that specific format of string...

SQL> ed
Wrote file afiedt.buf

  1  with t as (select 'a, b, c (x, y, z)' as txt from dual)
  2  --
  3  select txt, replace(regexp_replace(txt, '(^,)*\(.*\)','\1'),',')||regexp_replace(txt,'.*(\(.*\))','\1') as new_txt
  4* from t
SQL> /

TXT
-----------------
NEW_TXT
--------------------------------------------------------------------------------
a, b, c (x, y, z)
a b c (x, y, z)

But if your format of string differs then it's gonna be more complex as far as I can tell.

lurchmodeon You rang? lurchmodeoff

How about this?

WITH t AS (SELECT 'a, b, c (x, y, z)' col1 
             FROM dual)
SELECT t.col1
     , REGEXP_REPLACE(t.col1, '(\(.*\))|,', '\1') new_col
  FROM t
;               

COL1              NEW_COL
----------------- --------------------
a, b, c (x, y, z) a b c (x, y, z)

C.

Hi cd and BluShadow,

Thanks very much for your valuable help!

One other question - what if I want to replace the non-() enclosed commas with another string - such as "#". I tried your suggestion and got this:

WITH t AS (SELECT 'a, b, c (x, y, z)' col1 
             FROM dual)
SELECT t.col1
     , REGEXP_REPLACE(t.col1, '(\(.*\))|,', '\1') cds_awesome_solution
     , REGEXP_REPLACE(t.col1, '(\(.*\))|,', '#\1') pdaddys_futile_attempt1
     , REGEXP_REPLACE(t.col1, '(\(.*\))|,', '\1#') pdaddys_futile_attempt2
  FROM t
;

Result:

"COL1"	             "CDS_AWESOME_SOLUTION"   "PDADDYS_FUTILE_ATTEMPT1"   "PDADDYS_FUTILE_ATTEMPT2"
"a, b, c (x, y, z)"    "a b c (x, y, z)"        "a# b# c #(x, y, z)"        "a# b# c (x, y, z)#"

Notice how the pound is place before the left paren in attempt1 and placed after the right paren in attempt2? I know I could nest another regexp_replace - but I was wondering if a single pattern could suffice...

Thanks - and sorry I didn't make my question clear at all in my original post...

You guys ARE geniuses

Not sure about a single pattern, but at least without a 2nd regex_replace:

WITH t AS (SELECT 'a, b, c (x, y, z)' col1
             FROM DUAL)
SELECT t.col1,
       REPLACE(REGEXP_REPLACE(t.col1, '(\(.*\))|(,)', '\1\2\2'), ',,', '#') new_col
  FROM t;

COL1              NEW_COL
----------------- --------------------
a, b, c (x, y, z) a# b# c (x, y, z)

C.

Thanks!

That works perfectly!

(though I don't know HOW it works :( - I don't understand how the \1 backreference gets the part of the string before the parentheses... )

oh well - sometimes you have to just have faith :) - seeing is believing.

Message was edited by:
PDaddy

You have to think of regular expressions as a parser. Each position of the searched string is compared to each available pattern. The first "()" search pattern sort of protects that string against the second pattern.
Or you start thinking in regular expressions. ;-)

C.

Excelent solution! You may consider to add a ? (non greedy, restrictive mode) to cover the case there are more parentheses in the string.

<pre>
WITH t AS (SELECT 'a, b, c (x, y, z), a, (xx, yy, zz), x,' col1
FROM dual)
SELECT t.col1
, REGEXP_REPLACE(t.col1, '(\(.*?\))|,', '\1') new_col
FROM t
;

COL1 NEW_COL
--------------------------------------
a, b, c (x, y, z), a, (xx, yy, zz), x, a b c (x, y, z) a (xx, yy, zz) x
</pre>