Instead of trigger example - INSERT works but UPDATE and DELETE does not?

Question

Below is a demostration script of what I am trying to troubleshoot. Tests are done on 10gR2;
conn system/system
drop table tt purge ;
create table tt nologging as select * from all_users ;
alter table tt add constraint pk_tt_user_id primary key (user_id) nologging ;
analyze table tt compute statistics for table for all indexed columns ;
conn hr/hr
drop database link dblink ;
create database link dblink
connect to system identified by system
using 'xe.turkcell' ;
select * from global_name@dblink ;
drop view v_tt ;
create view v_tt as select username, user_id, created from tt@dblink order by 2 ;
select count(*) from v_tt ;
COUNT(*)
13
drop sequence seq_pk_tt_user_id ;
create sequence seq_pk_tt_user_id
minvalue 1000 maxvalue 99999
increment by 1;
create synonym tt for tt@dblink ;
CREATE OR REPLACE PROCEDURE prc_update_tt(old_tt v_tt%ROWTYPE, new_tt v_tt%ROWTYPE) IS
BEGIN
IF old_tt.user_id != new_tt.user_id THEN
RETURN; -- primary key
END IF;
IF old_tt.user_id IS NOT NULL AND new_tt.user_id IS NULL THEN
DELETE FROM tt
WHERE user_id = nvl(old_tt.user_id,
-99);
RETURN;
END IF;
IF (old_tt.username IS NULL AND new_tt.username IS NOT NULL) OR
(old_tt.username IS NOT NULL AND new_tt.username != old_tt.username) THEN
UPDATE tt
SET username = new_tt.username
WHERE user_id = nvl(old_tt.user_id,
-99);
END IF;
IF (old_tt.created IS NULL AND new_tt.created IS NOT NULL) OR
(old_tt.created IS NOT NULL AND new_tt.created != old_tt.created) THEN
UPDATE tt
SET created = new_tt.created
WHERE user_id = nvl(old_tt.user_id,
-99);
END IF;
END prc_update_tt;
CREATE OR REPLACE PROCEDURE prc_insert_tt(old_tt v_tt%ROWTYPE, new_tt v_tt%ROWTYPE) IS
new_tt_user_id NUMBER;
BEGIN
SELECT seq_pk_tt_user_id.NEXTVAL INTO new_tt_user_id FROM dual;
INSERT INTO tt
(username, user_id, created)
VALUES
(new_tt.username, new_tt_user_id, new_tt.created);
END prc_insert_tt;
CREATE OR REPLACE PROCEDURE prc_delete_tt(old_tt v_tt%ROWTYPE, new_tt v_tt%ROWTYPE) IS
BEGIN
DELETE FROM tt
WHERE user_id = nvl(old_tt.user_id,
-99);
END prc_delete_tt;
CREATE OR REPLACE TRIGGER trg_iof_v_tt
INSTEAD OF UPDATE OR INSERT OR DELETE ON v_tt
FOR EACH ROW
DECLARE
new_tt v_tt%ROWTYPE;
old_tt v_tt%ROWTYPE;
BEGIN
dbms_output.put_line('INSTEAD OF TRIGGER fired');
dbms_output.put_line(':NEW.user_id ' || :NEW.user_id);
dbms_output.put_line(':OLD.user_id ' || :OLD.user_id);
dbms_output.put_line(':NEW.username ' || :NEW.username);
dbms_output.put_line(':OLD.username ' || :OLD.username);
dbms_output.put_line(':NEW.created ' || :NEW.created);
dbms_output.put_line(':OLD.created ' || :OLD.created);
new_tt.user_id := :NEW.user_id;
new_tt.username := :NEW.username;
new_tt.created := :NEW.created;
old_tt.user_id := :OLD.user_id;
old_tt.username := :OLD.username;
old_tt.created := :OLD.created;
IF inserting THEN
prc_insert_tt(old_tt,
new_tt);
ELSIF updating THEN
prc_update_tt(old_tt,
new_tt);
ELSIF deleting THEN
prc_delete_tt(old_tt,
new_tt);
END IF;
END trg_iof_v_tt;
set serveroutput on
set null ^
insert into v_tt values ('XXX', -1, sysdate) ;
INSTEAD OF TRIGGER fired
:NEW.user_id -1
:OLD.user_id
:NEW.username XXX
:OLD.username
:NEW.created 30/01/2007
:OLD.created
1 row created.
commit ;
select * from v_tt where username = 'XXX' ;
USERNAME USER_ID CREATED
XXX 1000 31/01/2007          <- seems to be no problem with insert part but
update v_tt set username = 'YYY' where user_id = 1000 ;
INSTEAD OF TRIGGER fired
:NEW.user_id
:OLD.user_id
:NEW.username YYY
:OLD.username
:NEW.created
:OLD.created
1 row updated.
commit ;
select count(*) from v_tt where username = 'YYY' ;
COUNT(*)
0               <- here is my first problem with update part, Oracle said "1 row updated."
delete from v_tt where user_id = 1000 ;
INSTEAD OF TRIGGER fired
:NEW.user_id
:OLD.user_id
:NEW.username
:OLD.username
:NEW.created
:OLD.created
1 row deleted.
commit ;
select count(*) from v_tt ;
COUNT(*)
14               <- here is my second problem with delete part, Oracle said "1 row deleted."
Any comments will be welcomed, thank you.
Message was edited by:
TongucY
changed "-1" values to "1000" in the where clause of delete and update statements.
it was a copy/paste mistake, sorry for that.

Answer 1

What table do you process in your procedures ? You don't use DBLINK to
reference remote table in your procedures.
Seems, you have table "TT" in "HR" schema too.
Look:
SQL> create table tt nologging as select * from all_users where rownum <=3;
Table created.
SQL> select * from tt;
USERNAME                          USER_ID CREATED
SYS                                     0 25-APR-06
SYSTEM                                  5 25-APR-06
OUTLN                                  11 25-APR-06
SQL> conn scott/tiger
Connected.
SQL> create database link lk65 connect to ... identified by ... using 'nc65';
Database link created.
SQL> select * from tt@lk65;
USERNAME                          USER_ID CREATED
SYS                                     0 25-APR-06
SYSTEM                                  5 25-APR-06
OUTLN                                  11 25-APR-06
SQL> create view v_tt as select username, user_id, created from tt@lk65 order by 2;
View created.
SQL> select * from v_tt;
USERNAME                          USER_ID CREATED
SYS                                     0 25-APR-06
SYSTEM                                  5 25-APR-06
OUTLN                                  11 25-APR-06
SQL> create sequence seq_pk_tt_user_id
  2  minvalue 1000 maxvalue 99999
  3  increment by 1;
Sequence created.
SQL> CREATE OR REPLACE PROCEDURE prc_insert_tt(old_tt v_tt%ROWTYPE, new_tt v_tt%ROWTYPE) IS
  2  new_tt_user_id NUMBER;
  3  BEGIN
  4  SELECT seq_pk_tt_user_id.NEXTVAL INTO new_tt_user_id FROM dual;
  5  INSERT INTO tt
  6  (username, user_id, created)
  7  VALUES
  8  (new_tt.username, new_tt_user_id, new_tt.created);
  9  END prc_insert_tt;
10  /
Warning: Procedure created with compilation errors.
SQL> show error
Errors for PROCEDURE PRC_INSERT_TT:
LINE/COL ERROR
5/1      PL/SQL: SQL Statement ignored
5/13     PL/SQL: ORA-00942: table or view does not exist
SQL> edit
Wrote file afiedt.buf
  1  CREATE OR REPLACE PROCEDURE prc_insert_tt(old_tt v_tt%ROWTYPE, new_tt v_tt%ROWTYPE) IS
  2  new_tt_user_id NUMBER;
  3  BEGIN
  4  SELECT seq_pk_tt_user_id.NEXTVAL INTO new_tt_user_id FROM dual;
  5  INSERT INTO tt@lk65
  6  (username, user_id, created)
  7  VALUES
  8  (new_tt.username, new_tt_user_id, new_tt.created);
  9* END prc_insert_tt;
SQL> /
Procedure created.Rgds.