How to fetch a ref_cursor into Oracle's WITH CLAUSE - oracle

Question

Is it possible to use a ref_cursor with ORACLE WITH CLAUSE. For example, I have the following scenario. First I have a procedure which returns a ref_cursor
PROCEDURE p_return_cursor(p_id IN NUMBER, io_cursor OUT t_cursor)
AS
BEGIN
OPEN io_cursor FOR
SELECT col1, col2
FROM Table1 t
WHERE t.id = p_id;
END;
Second, I have another procedure on which I make a call to p_return_cursor:
PROCEDURE p_test(p_cid IN NUMBER)
AS
l_cursor t_cursor;
l_rec Table1%ROWTYPE;
BEGIN
p_return_cursor(p_id => p_cid, io_cursor => l_cursor);
-- CODE GOES HERE
...
Now, my question is, can I make a temp table using the Oracle's WITH CLAUSE using the cursor; something like:
...
WITH data AS (
LOOP
FETCH l_cursor INTO l_rec;
EXIT WHEN l_cursor%NOTFOUND;
SELECT l_rec.col1, l_rec.col2 FROM DUAL;
END LOOP;
CLOSE l_cursor;
)

Answer 1

You cannot do it directly. You can, however, BULK COLLECT your cursor into a PL/SQL table variable and use that in a WITH clause.
Be careful of memory usage if the cursor contains many rows.
Full example:
CREATE TABLE table1 ( col1 NUMBER, col2 NUMBER );
INSERT INTO table1 ( col1, col2 ) SELECT rownum, 100+rownum FROM DUAL CONNECT BY ROWNUM <= 15;
COMMIT;
CREATE OR REPLACE PACKAGE se_example AS
TYPE t_cursor IS REF CURSOR
RETURN table1%ROWTYPE;
TYPE l_rec_tab IS TABLE OF table1%ROWTYPE;
PROCEDURE p_test (p_cid IN NUMBER);
END se_example;
CREATE OR REPLACE PACKAGE BODY se_example AS
-- private
PROCEDURE p_return_cursor (p_id IN NUMBER, io_cursor OUT t_cursor) AS
BEGIN
OPEN io_cursor FOR
SELECT col1,
col2
FROM table1 t;
--WHERE t.id = p_id; -- I didn't put "id" column in my sample table, sorry...
END p_return_cursor;
PROCEDURE p_test (p_cid IN NUMBER) IS
l_cursor t_cursor;
l_tab l_rec_tab;
l_dummy NUMBER;
BEGIN
p_return_cursor (p_id => p_cid, io_cursor => l_cursor);
FETCH l_cursor BULK COLLECT INTO l_tab;
-- *** instead of this
-- WITH data AS (
-- LOOP
-- FETCH l_cursor INTO l_rec;
-- EXIT WHEN l_cursor%NOTFOUND;
-- SELECT l_rec.col1, l_rec.col2 FROM DUAL;
-- END LOOP;
-- CLOSE l_cursor;
-- )
-- '
--
-- *** do this
WITH data AS
( SELECT col1, col2 FROM TABLE(l_tab) )
SELECT sum(col1 * col2) INTO l_dummy
FROM data;
dbms_output.put_line('result is ' || l_dummy);
END p_test;
END se_example;
begin
se_example.p_test(100);
end;