parsing JSON string in oracle - json

Question

i have JSON string in one column in oracle 10g database like
[{"id":"1","contactBy":"Rajesh Kumar"},{"id":"2","contactBy":"Rakesh Kumar"}]
I have to get the value for ContactBy in that column for one of the reports.
is there any built in function to parse the JSON string in Oracle 10g or any user defined funciton to parse the String

Answer 1

As said by Jens in comments, JSON support is only available from 12c, but you can use regular expressions as a workaround to get what you want:
select regexp_replace(regexp_substr('[{"id": "1", "contactBy":"Rajesh Kumar"},{"id": "2","contactBy": "Emmanuel Test"}]',
'"contactBy":\s*("(\w| )*")', 1, level),
'"contactBy":\s*"((\w| )*)"', '\1', 1, 1) contact
from dual
connect by regexp_substr('[{"id": "1","contactBy":"Rajesh Kumar"},{"id": "2","contactBy": "Emmanuel Test"}]', '"contactBy":\s*("(\w| )*")', 1, level) is not null
;
EDIT : request modified to take both special characters and display answers in a single row:
select listagg(contact, ', ') within group (order by lev)
from
(
select regexp_replace(regexp_substr('[{"id": "1", "contactBy":"Rajesh Kumar"},{"id": "2","contactBy": "Emmanuel Test+-"}]',
'"contactBy":\s*(".*?")', 1, level),
'"contactBy":\s*"(.*?)"', '\1', 1, 1) contact, level lev
from dual
connect by regexp_substr('[{"id": "1","contactBy":"Rajesh Kumar"},{"id": "2","contactBy": "Emmanuel Test+-"}]', '"contactBy":\s*(".*?")', 1, level) is not null
)
;

Answer 2

# Emmanuel your code is really helped a lot, thank you very much. but your query is taking too much of time, so i changed to a function , which will return the required values.
CREATE OR REPLACE FUNCTION SFGETCRCONTACTBY(INCRID NUMBER) RETURN VARCHAR2 AS
TEMPINT NUMBER :=0;
OUTPUT VARCHAR2(10000) ;
TEMPVAR VARCHAR2(1000);
BEGIN
SELECT REGEXP_COUNT(CR_CONTACT_BY, '"contactBy":\S*(".*?")')
INTO TEMPINT
FROM T_LOAN_REQUEST_MARKET WHERE CR_ID=INCRID;
WHILE TEMPINT > 0
LOOP
SELECT REGEXP_REPLACE(REGEXP_SUBSTR(CR_CONTACT_BY, '"contactBy":\S*(".*?")', 1,TEMPINT), '"contactBy":\S*"(.*?)"', '\1', 1, 1) INTO TEMPVAR
FROM T_LOAN_REQUEST_MARKET WHERE CR_ID=INCRID;
IF OUTPUT IS NULL THEN
OUTPUT := TEMPVAR;
ELSE
OUTPUT := OUTPUT ||',' || TEMPVAR;
END IF;
TEMPINT := TEMPINT-1;
END LOOP;
RETURN OUTPUT;
END;
/