Live ORACLE

DECLARE
TYPE nested_typ IS TABLE OF NUMBER;
nt1 nested_typ := nested_typ(1,2,3);
nt2 nested_typ := nested_typ(3,2,1);
nt3 nested_typ := nested_typ(2,3,1,3);
nt4 nested_typ := nested_typ(1,2,4);
answer BOOLEAN;
howmany NUMBER;
PROCEDURE testify(truth BOOLEAN DEFAULT NULL, quantity NUMBER DEFAULT NULL) IS
BEGIN
IF truth IS NOT NULL THEN
DBMS_OUTPUT.PUT_LINE(CASE truth WHEN TRUE THEN 'True' WHEN FALSE THEN
'False' END);
END IF;
IF quantity IS NOT NULL THEN
DBMS_OUTPUT.PUT_LINE(quantity);
END IF;
END;
BEGIN
answer := nt1 IN (nt2,nt3,nt4); -- true, nt1 matches nt2
testify(truth => answer);
answer := nt1 SUBMULTISET OF nt3; -- true, all elements match
testify(truth => answer);
answer := nt1 NOT SUBMULTISET OF nt4; -- also true
testify(truth => answer);
howmany := CARDINALITY(nt3); -- number of elements in nt3
testify(quantity => howmany);
howmany := CARDINALITY(SET(nt3)); -- number of distinct elements
testify(quantity => howmany);
answer := 4 MEMBER OF nt1; -- false, no element matches
testify(truth => answer);
answer := nt3 IS A SET; -- false, nt3 has duplicates
testify(truth => answer);
answer := nt3 IS NOT A SET; -- true, nt3 has duplicates
testify(truth => answer);
answer := nt1 IS EMPTY; -- false, nt1 has some members
testify(truth => answer);
END;
/

Comparing Nested Tables with Set Operators