Difference of two collections - plsql

Question

I'm trying to get a difference of two collections however every time getting below exception. Kindly help. My sample code is also available below. Not sure what's going wrong here... can MULTISET EXCEPT not be applied on RECORD types?
PLS-00306: wrong number or types of arguments in call to
'MULTISET_EXCEPT_ALL'
DECLARE
TYPE FRND_OBJ IS RECORD
(
FrndID NUMBER,
JOBID NUMBER,
REGIONID NUMBER,
COLLEGEID NUMBER
);
TYPE FRND_LIST IS TABLE OF FRND_OBJ;
CURSOR c_date_rolling
IS
SELECT 1,
2,
3,
4
FROM DUAL;
lv_roll_date FRND_LIST;
lv_roll_date_full FRND_LIST;
lv_roll_date_delta FRND_LIST;
g_error_msg VARCHAR2 (1500);
BEGIN
SELECT 5,
6,
7,
8
BULK COLLECT INTO lv_roll_date_full
FROM DUAL;
OPEN c_date_rolling;
FETCH c_date_rolling BULK COLLECT INTO lv_roll_date;
CLOSE c_date_rolling;
DBMS_OUTPUT.put_line ('Full Count: ' || lv_roll_date_full.COUNT);
DBMS_OUTPUT.put_line ('Rolling Count: ' || lv_roll_date.COUNT);
lv_roll_date_delta := lv_roll_date_full MULTISET EXCEPT lv_roll_date;
DBMS_OUTPUT.put_line (lv_roll_date_delta.COUNT);
EXCEPTION
WHEN NO_DATA_FOUND
THEN
g_error_msg :=
SUBSTR (SQLERRM, 1, 200)
|| SUBSTR (DBMS_UTILITY.FORMAT_ERROR_BACKTRACE, 20);
DBMS_OUTPUT.PUT_LINE (g_error_msg);
WHEN OTHERS
THEN
g_error_msg :=
SUBSTR (SQLERRM, 1, 200)
|| SUBSTR (DBMS_UTILITY.FORMAT_ERROR_BACKTRACE, 20);
DBMS_OUTPUT.PUT_LINE (g_error_msg);
END;
/

Answer 1

Here is explained, that you will need a MAP or ORDER method. In your sample:
CREATE OR REPLACE TYPE frnd_obj
AUTHID DEFINER AS OBJECT
(
frndid NUMBER,
jobid NUMBER,
regionid NUMBER,
collegeid NUMBER,
MAP MEMBER FUNCTION tostring
RETURN VARCHAR2
)
/
SHOW ERRORS;
CREATE OR REPLACE TYPE BODY frnd_obj AS
MAP MEMBER FUNCTION tostring
RETURN VARCHAR2 IS
BEGIN
RETURN TO_CHAR (frndid) || ';' || TO_CHAR (jobid) || ';' || TO_CHAR (regionid) || ';' || TO_CHAR (collegeid);
END tostring;
END;
/
CREATE TYPE FRND_LIST IS TABLE OF FRND_OBJ;
And now you can use it:
DECLARE
-- TYPE FRND_OBJ IS RECORD
-- (
-- FrndID NUMBER,
-- JOBID NUMBER,
-- REGIONID NUMBER,
-- COLLEGEID NUMBER
-- );
-- TYPE FRND_LIST IS TABLE OF FRND_OBJ;
CURSOR c_date_rolling
IS
SELECT FRND_OBJ(1,
2,
3,
4)
FROM DUAL;
-- union all
-- SELECT FRND_OBJ(5,
-- 6,
-- 7,
-- 8)
-- FROM DUAL;
lv_roll_date FRND_LIST;
lv_roll_date_full FRND_LIST;
lv_roll_date_delta FRND_LIST;
g_error_msg VARCHAR2 (1500);
BEGIN
SELECT FRND_OBJ(5,
6,
7,
8)
BULK COLLECT INTO lv_roll_date_full
FROM DUAL;
OPEN c_date_rolling;
FETCH c_date_rolling BULK COLLECT INTO lv_roll_date;
CLOSE c_date_rolling;
DBMS_OUTPUT.put_line ('Full Count: ' || lv_roll_date_full.COUNT);
DBMS_OUTPUT.put_line ('Rolling Count: ' || lv_roll_date.COUNT);
lv_roll_date_delta := lv_roll_date_full MULTISET EXCEPT ALL lv_roll_date;
DBMS_OUTPUT.put_line (lv_roll_date_delta.COUNT);
EXCEPTION
WHEN NO_DATA_FOUND
THEN
g_error_msg :=
SUBSTR (SQLERRM, 1, 200)
|| SUBSTR (DBMS_UTILITY.FORMAT_ERROR_BACKTRACE, 20);
DBMS_OUTPUT.PUT_LINE (g_error_msg);
WHEN OTHERS
THEN
g_error_msg :=
SUBSTR (SQLERRM, 1, 200)
|| SUBSTR (DBMS_UTILITY.FORMAT_ERROR_BACKTRACE, 20);
DBMS_OUTPUT.PUT_LINE (g_error_msg);
END;
/