How to update reference oracle - sql

Question

Im making two object tables, with reference M:M, insert is working correctly, but when im trying to update reference, i get the error.
Error:
SQL Error: ORA-00904: "A"."ATS_PN": "%s: invalid identifier"
CREATE OR REPLACE TYPE STUDENTI AS OBJECT(
S_NUM INT,
S_UZV VARCHAR2(30)
);
CREATE OR REPLACE TYPE PASNIEDZEJI AS OBJECT(
P_NUM INT,
P_UZV VARCHAR2(30)
);
CREATE OR REPLACE TYPE ATS_ST AS OBJECT(
ID INT,
ST_ID REF STUDENTI
);
CREATE OR REPLACE TYPE ATS_PN AS OBJECT(
ID INT,
PN_ID REF PASNIEDZEJI
);
CREATE OR REPLACE TYPE ATS_P AS TABLE OF ATS_PN;
CREATE OR REPLACE TYPE ATS_S AS TABLE OF ATS_ST;
CREATE OR REPLACE TYPE O_STUDENTI AS OBJECT(
STUD STUDENTI,
PASN ATS_P
);
CREATE OR REPLACE TYPE O_PASNIEDZEJI AS OBJECT(
PASN PASNIEDZEJI,
STUD ATS_S
);
CREATE TABLE T_STUDENTI OF O_STUDENTI
NESTED TABLE PASN STORE AS P_TBL;
CREATE TABLE T_PASNIEDZEJI OF O_PASNIEDZEJI
NESTED TABLE STUD STORE AS S_TBL;
INSERT INTO T_STUDENTI VALUES (STUDENTI(191, 'BRONES'), NULL);
INSERT INTO T_PASNIEDZEJI VALUES (PASNIEDZEJI(53, 'JHONES'), NULL);
INSERT INTO T_PASNIEDZEJI VALUES (PASNIEDZEJI(54, 'HIKKAEV'), NULL);
UPDATE T_STUDENTI A SET A.PASN = (1, 'TEST') WHERE A.STUD.S_NUM = 191; --misstake some where ther :/

Answer 1

I'm not following what you are doing functionally, but I've removed the REF from your objects because it's hard to deal with in SQL.
You'll notice that t_studenti.pasn is ats_p which is a table of ats_pn which contains an id and a pasniedzeji: you must construct that entire hierarchy.
This code will let you update the table:
CREATE OR REPLACE TYPE STUDENTI AS OBJECT(
S_NUM INT,
S_UZV VARCHAR2(30)
);
CREATE OR REPLACE TYPE PASNIEDZEJI AS OBJECT(
P_NUM INT,
P_UZV VARCHAR2(30)
);
CREATE OR REPLACE TYPE ATS_ST AS OBJECT(
ID INT,
ST_ID STUDENTI
);
CREATE OR REPLACE TYPE ATS_PN AS OBJECT(
ID INT,
PN_ID PASNIEDZEJI
);
CREATE OR REPLACE TYPE ATS_P AS TABLE OF ATS_PN;
CREATE OR REPLACE TYPE ATS_S AS TABLE OF ATS_ST;
CREATE OR REPLACE TYPE O_STUDENTI AS OBJECT(
STUD STUDENTI,
PASN ATS_P
);
CREATE OR REPLACE TYPE O_PASNIEDZEJI AS OBJECT(
PASN PASNIEDZEJI,
STUD ATS_S
);
CREATE TABLE T_STUDENTI OF O_STUDENTI
NESTED TABLE PASN STORE AS P_TBL;
CREATE TABLE T_PASNIEDZEJI OF O_PASNIEDZEJI
NESTED TABLE STUD STORE AS S_TBL;
INSERT INTO T_STUDENTI VALUES (STUDENTI(191, 'BRONES'), NULL);
INSERT INTO T_PASNIEDZEJI VALUES (PASNIEDZEJI(53, 'JHONES'), NULL);
INSERT INTO T_PASNIEDZEJI VALUES (PASNIEDZEJI(54, 'HIKKAEV'), NULL);
UPDATE t_studenti a
SET a.pasn = ats_p(ats_pn(1, -- ??
pasniedzeji(1,
'TEST')))
WHERE a.stud.s_num = 191;